Case#: male; age 44

DiseaseAssertion: Hypertrophic, restrictive, and dilated cardiomyopathy

FamilyInfo: The patient’s unaffected 6-year-old daughter was tested for the variant. His brother and parents were healthy

ParentalTesting: Parents refused genetic testing

CasePresentingHPOs: HP:0001639 HP:0001723 HP:0001644

CaseHPOFreeText: Hypertrophic cardiomyopathy; restrictive left-ventricular filling pattern; diastolic dysfunction

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: 25-gene Ion AmpliSeq panel with Ion PGM semiconductor sequencing; Sanger sequencing

FunctionalAnalysis: NR

Variant: TPM1 c.292G>A (p.Glu98Lys; p.E98K; rs730881131); missense variant; heterozygous

ClinVar: 1472862

CAID: CA392720843

gnomAD: NR

Case#: 29 year old female; diagnosed with DCM 8 years before death; died suddenly at home on 22 February 2017; forensic autopsy case

DiseaseAssertion: Dilated cardiomyopathy (DCM) with sudden cardiac death; MYBPC3-related

FamilyInfo: Family from Central-South China with a history of SCD. Father (I:1) reportedly died of a heart attack at 37, not genetically tested. Mother (I:2) and sister (II:2) are unaffected and do not carry the variant. No other affected relatives reported.

ParentalTesting: Not performed, both parents were not genotyped for the variant; the father was deceased before the study. Maternal non-carriage confirmed by Sanger, so the variant is either paternal or de novo; phase not established.

CasePresentingHPOs: HP:0001644; HP:0001645

CaseHPOFreeText: Diagnosed with DCM 8 years before death, with no other abnormalities. Found unresponsive at home at noon and expired; no prodromal symptoms documented. Autopsy: enlarged heart with valve thickening, myocardial fibrosis, and multi-organ congestion; no other fatal injury or disease. HE staining of left ventricle showed no hypertrophy or other anomalies. Toxicological screening for ethanol, benzodiazepines, barbiturates, amphetamine, methamphetamine, ketamine, morphine, MDMA, and THC-acid was negative; serum IgE normal (27 IU/ml); eosinophils 4.7% with no mast-cell degranulation.

CaseNotHPOs: HP:0001639; HP:0001634; HP:0003124

CaseNotHPOFreeText: No cardiomyocyte hypertrophy on histology, distinguishing this from HCM. No coronary, valvular, or congenital structural disease identified. No toxicological cause of death.

CasePreviousTesting: Whole-exome sequencing on postmortem blood, retaining synonymous variants; filtering against gnomAD and CMDB; in silico prediction with MutationTaster, PolyPhen-2, and SIFT; NetGene2-2.42 used to predict splice effects. Five variants in cardiomyopathy-related genes were found; only the MYBPC3 variant was classified likely pathogenic.

Genotyping Method: WES with Sanger confirmation on ABI 3100; family members genotyped by Sanger.

FunctionalAnalysis: Minigene assay pcDNA3.1-MYBPC3 construct spanning exon 1-intron 1-exon 2, transfected into HEK293 cells: wild-type and the c.10G>A negative control both produced a ~1,500 bp full-length band and a ~300 bp spliceosome band; the c.24A>C construct produced no spliceosome band, indicating abnormal splicing with intron 1 retention and frameshift. Immunohistochemistry showed decreased MYBPC3 protein in the proband's left ventricle versus a control heart.

Variant: MYBPC3 NM_000256.3:c.24A>C (p.Pro8Pro); heterozygous synonymous variant at the penultimate base of exon 1; disrupts the splice donor site; novel

ClinVar: 164098

CAID: CA11138

gnomAD: 0.00001541

AdditionalInfo: Classified likely pathogenic with PS3, PM2, PP1, PP3; note the paper's Discussion relabels the prediction code as PP4, an internal inconsistency. The authors describe it as the first reported deleterious synonymous MYBPC3 variant, acting by intron retention and reduced protein. The same splice site is affected by the known HCM variants c.24+1G>A and c.24+3A>C. Four other variants were found and classified likely benign or VUS: LDB3 c.2131T>C (VUS), BBS2 c.422A>G, EVC2 c.2643G>C, and BBS4 c.1548_1549del.

Case#: E01

DiseaseAssertion: Early onset Hypertrophic Cardiomyopathy

FamilyInfo: Familiarity case reported as "yes"

ParentalTesting: Not reported

CasePresentingHPOs: HP:0001639

CaseHPOFreeText: Early-onset hypertrophic cardiomyopathy

CaseNotHPOs: Not reported

CaseNotHPOFreeText: Not reported

CasePreviousTesting: Not reported

Genotyping Method: Next Generation Sequencing

FunctionalAnalysis: Not reported

Variant: MYBPC3 c.553A>T (p.Lys185Ter)

ClinVar: 574262

CAID: Not found

gnomAD: 11-47349875-T-G

AdditionalInfo: Clinical significance: known/pathogenic. Allele coverage 202.

Case#: E027

DiseaseAssertion: Early onset hypertrophic cardiomyopathy

FamilyInfo: Familiarity case reported as "yes"

ParentalTesting: Not reported

CasePresentingHPOs: HP:0001639

CaseHPOFreeText: Not reported

CaseNotHPOs: Not reported

CaseNotHPOFreeText: Not reported

CasePreviousTesting: Not reported

Genotyping Method: Next Generation Sequencing

FunctionalAnalysis: Not reported

Variant: c.794A>T (Lys265Ile)

ClinVar: Not found

CAID: CA005099

gnomAD: Not found

AdditionalInfo: Clinical significance: known/uncertain significance. Allele coverage: 193.

Case#: E030

DiseaseAssertion: Early onset hypertrophic cardiomyopathy

FamilyInfo: Familiarity case reported as "yes"

ParentalTesting: Not reported

CasePresentingHPOs: HP:0001639

CaseHPOFreeText: Not reported

CaseNotHPOs: Not reported

CaseNotHPOFreeText: Not reported

CasePreviousTesting: Not reported

Genotyping Method: Next Generation Sequencing

FunctionalAnalysis: Not reported

Variant: c.431T>A (Leu144Gln)

ClinVar: Not found

CAID: Not found

gnomAD: Not found

AdditionalInfo: Clinical Significance: Known/pahtogenic. Allele coverage: 227.

Case#: E034

DiseaseAssertion: Early onset hypertrophic cardiomyopathy

FamilyInfo: Familiarity case reported as "yes"

ParentalTesting: Not reported

CasePresentingHPOs: HP:0001639

CaseHPOFreeText: Not reported

CaseNotHPOs: Not reported

CaseNotHPOFreeText: Not reported

CasePreviousTesting: Not reported

Genotyping Method: Next Generation Sequencing

FunctionalAnalysis: Not reported

Variant: c.281G>C (Arg94Thr)

ClinVar: Not found

CAID: CA004216

gnomAD: Not found

AdditionalInfo: Clinical Significance: Known/uncertain significance. Allele coverage 196

Case#: L08

DiseaseAssertion: Late onset hypertrophic cardiomyopathy

FamilyInfo: Familiarity case reported as "yes"

ParentalTesting: Not reported

CasePresentingHPOs: HP:0001639

CaseHPOFreeText: Not reported

CaseNotHPOs: Not reported

CaseNotHPOFreeText: Not reported

CasePreviousTesting: Not reported

Genotyping Method: Next Generation Sequencing

FunctionalAnalysis: Not reported

Variant: c.1624G>C (Glu542Gln), heterozygous, pathogenic. c.385C>G (Thr128Ser) heterozygous, likely benign.

ClinVar: Not found

CAID: CA407440771 (MYBPC3 CAID not found)

gnomAD: Not found

AdditionalInfo: L08 has two variants. MYBPC3 variant missense/splicing, known pathogenic; Allele coverage 188. TNNI3 variant Missense, new/likely benign; Allele coverage 400.

Case#: female; age 65

DiseaseAssertion: chemotherapy-induced cardiomyopathy with severe left ventricular systolic dysfunction

FamilyInfo: NR

ParentalTesting: NR

CasePresentingHPOs: HP:0001644 HP:0001635 HP:0001640

CaseHPOFreeText: Dilated left ventricle; left ventricular dysfunction; cardiomegaly; bilateral pleural effusion; dyspnea

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: Previous anthracycline-associated cardiomyopathy 7 years earlier

Genotyping Method: TruSight One Expanded 6700-gene sequencing panel on an Illumina NextSeq 550

FunctionalAnalysis: NR

Variant: c.452G>A (p.Arg151Gln; rs730881101); missense variant; heterozygous

ClinVar: 181617

CAID: NR

gnomAD: NR

Case1: Caucasian. Sex and exact age not specified for the proband

DiseaseAssertion: Dilated cardiomyopathy (DCM)

FamilyInfo: Family A was notable for severe HF and sudden death in young children. Individuals I-2, III-10 and IV-7 died suddenly at ages 3 years, 13 months, and 5 months respectively, without prior evidence of heart disease. Two siblings, IV-5 and IV-8, presented with DCM and advanced HF at 5 months of age (LVEF 27% and 29%). Individuals III-3 and IV-1 developed end-stage HF refractory to medical therapy as teenagers. III-3 presented at age 13 with refractory HF, underwent mitral and tricuspid valve replacement for functional regurgitation and died weeks later of multisystem organ failure. IV-1 was asymptomatic when diagnosed with DCM at 7 years during family screening, but developed severe HF at age 17 and underwent transplant at 18 years of age. Individuals III-4, III-7 and III-12 developed mild exercise intolerance in their 5th decade.

ParentalTesting: NR

CasePresentingHPOs: HP:0001635, HP:0001644

CaseHPOFreeText: No family members with TPM1 D230N had evidence of cardiac conduction disease, and with one exception, none had evidence of skeletal myopathy

CaseNotHPOs: NR

CaseNotHPOFreeText: No family members with TPM1 D230N had evidence of cardiac conduction disease, and with one exception, none had evidence of skeletal myopathy.

CasePreviousTesting: No prior testing.

Genotyping Method: Genomic DNA was isolated from blood using standard methods in probands with DCM. Direct DNA sequence analysis of all coding regions and intron/exon boundaries was performed in 6 sarcomere genes.

FunctionalAnalysis: Functional analysis performed on recombinant proteins but not patient tissue. In vitro studies demonstrated major inhibitory effects on sarcomere function with reduced Ca2+-sensitivity, maximum activation, and Ca2+ affinity compared to wildtype TPM1.

Variant: NM_000366.5:c.688G>A (p.Asp230Asn)

ClinVar: NR

CAID: UnregisteredVariant

gnomAD: NR

AdditionalInfo: The paper does not explicitly identify which pedigree member is the Family A proband

Case2: Caucasian. Sex and exact age not specified for the proband

DiseaseAssertion: Dilated cardiomyopathy (DCM)

FamilyInfo: Young members of this family also presented with severe HF. Individual III-1 developed failure to thrive at 10 weeks of age and echocardiography revealed severe LV dilation (LVIDD Z-score 15.6) and systolic dysfunction (LVEF 15%). Transplantation was considered, but she had substantial recovery with basic medical therapy. By age 8 years, she was asymptomatic with only mild LV systolic dysfunction (LVIDD Z-score 1.3, LVEF 46%). At age 20, II-6 underwent cardiac transplantation shortly after presenting with refractory HF symptoms and severe LV systolic dysfunction (LVEF < 20%). Individual II-7 died of HF at 12 years, prior to genetic testing. In addition to DCM, he had congenital cataracts and skeletal muscle weakness. I-1 had unexplained syncope at age 56 years. Cardiac studies revealed ventricular tachycardia and DCM (LVEF 25%) which improved with medical management. Three other adults (II-2, II-3, II-4, ages 38, 36 and 33 years, respectively) had asymptomatic LV systolic dysfunction.

ParentalTesting: NR

CasePresentingHPOs: HP:0001635, HP:0001644

CaseHPOFreeText: NR

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: No prior testing.

Genotyping Method: Genomic DNA was isolated from blood using standard methods in probands with DCM. Direct DNA sequence analysis of all coding regions and intron/exon boundaries was performed in 6 sarcomere genes.

FunctionalAnalysis: Functional analysis performed on recombinant proteins but not patient tissue. In vitro studies demonstrated major inhibitory effects on sarcomere function with reduced Ca2+-sensitivity, maximum activation, and Ca2+ affinity compared to wildtype TPM1.

Variant: NM_000366.5:c.688G>A (p.Asp230Asn)

ClinVar: NR

CAID: UnregisteredVariant

gnomAD: NR

AdditionalInfo: The paper does not explicitly identify which pedigree member is the Family B proband

Case1: 63-year-old male

DiseaseAssertion: Atrial flutter(54), VT & ICD(57); CVA(58) & DCM(58); HF(59)

FamilyInfo: There are 14 affected family members (Fig 1): six living (three sisters III-1, III-4, III-6 and three nieces IV-5, IV-15, IV-16) and eight deceased individuals (I-3, II-8, II-13, III-8, III-10, IV-1, IV-4, IV-6).

ParentalTesting:

CasePresentingHPOs:

CaseHPOFreeText: atrial flutter during evaluation for non-cardiac surgery. Subsequent evaluations led to the diagnosis of SSS. At 54 years old, echocardiogram showed mild systolic dysfunction and left ventricle dilation (EF 45%, LVEDD 58 mm). Myocardial perfusion study showed exercise intolerance but no signs of ischemia. At presentation, he felt well noting mild exercise intolerance for the past year with no palpitations or chest pain; he took no medications. At age 49, he had normal systolic function and LV dilation by echocardiogram (EF 53%, LVEDD 61 mm) and a normal myocardial perfusion study.

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: Sanger sequencing

FunctionalAnalysis: NR

Variant: NM_170707.4(LMNA):c.357-2A>G

ClinVar: 652066

CAID: CA342814936

gnomAD: NR

AdditionalInfo:

Case#: 43-year-old man family b

DiseaseAssertion: Familial dilated cardiomyopathy (FDCM)

FamilyInfo: Sister II:1 had previously been diagnosed with DCM and carried both reported variants. Brother II:2 died of sudden cardiac death.

ParentalTesting: father was negative for either varient

CasePresentingHPOs: HP:0031352, HP:0002094, HP:0002321 HP:0001644 “Dyspnea; chest tightness; dizziness; dilated cardiomyopathy

CaseHPOFreeText: Severe DCM symptoms

CaseNotHPOs: not reported

CaseNotHPOFreeText: Father I:1 and daughter III:1 were reported to have no clinical symptoms

CasePreviousTesting: Previously diagnosed with FDCM

Genotyping Method: NGS. PCR, Sanger

FunctionalAnalysis: Putative pathogenic mutations were analysed computationally using the PolyPhen-2, SIFT, and MutationTaster

Variant: MYH7 NM_000257:c.3134G>A; p.Arg1045His; heterozygous missense

ClinVar: 651054

CAID: N/A

gnomAD: 14-23422291-C-T

AdditionalInfo: two variants may have a “dose effect” and associate their combination with the proband’s severe phenotype

Case#:44-year-old woman , family 1 proband

DiseaseAssertion: Familial hypertrophic cardiomyopathy

FamilyInfo: Father, sister, and brother, died of sudden cardiac death around age 40

ParentalTesting: not reported

CasePresentingHPOs: HP:0031352, HP:0002094, HP:0005144 “Dyspnea; chest tightness, increased interventricular septum thickness”

CaseHPOFreeText: Symptoms after exercise, interventricular septum thickness 14.8 mm; left atrium 32 mm.

CaseNotHPOs: not reported

CaseNotHPOFreeText:not reported

CasePreviousTesting: no previous testing was reported

Genotyping Method: NGS. PCR, Sanger

FunctionalAnalysis: Putative pathogenic mutations were analysed computationally using the PolyPhen-2, SIFT, and MutationTaster

Variant: TNNI3 NM_000363.4:c.433C>G; p.Arg145Gly heterozygous exon 7 missense

ClinVar:12419

CAID: N/A

gnomAD: 19-55154146-G-C

AdditionalInfo: reported variant and a potential HCM hotspot

Case1: 45 year old man, Chinese Han descent

DiseaseAssertion: Symptoms of congestive heart failure for 10 years and then developed ascites

FamilyInfo: No obvious family history.

ParentalTesting: NR

CasePresentingHPOs: HP:0031295, HP:0030718, HP:0001639

CaseHPOFreeText: typical RCM phenotype with biatrial enlargement, normal LV volume and wall thickness, mildly depressed LV ejection fraction (52%), and significantly impaired LV diastolic function

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: high-throughput NGS

FunctionalAnalysis: NR

Variant: NM_000256.3(MYBPC3):c.1000G>A (p.Glu334Lys)

ClinVar: 177902

CAID: CA009667

gnomAD: 11-47367848-C-T

AdditionalInfo: NR

Case 1: One proband; (53-year-old woman)

DiseaseAssertion: Hypertrophic cardiomyopathy (HCM) with fasciculoventricular bypass tract (FVBT)

FamilyInfo: Autosomal dominant family with HCM and pre-excitation. Mother has an ICD for nonischemic cardiomyopathy and progressed from HCM to DCM; sister (49) carries the variant with HCM and NSVT; younger daughter (25) carries the variant with pre-excitation but no HCM. Maternal aunt died suddenly at 42; maternal uncle had a sudden cardiac arrest at 40 with subsequent ICD.

CasePresentingHPOs: HP:0001962; HP:0001639; HP:0004756; HP:0001677; HP:0001671; HP:0004308

CaseHPOFreeText: Palpitations prompted workup. ECG showed pre-excitation; Holter documented NSVT; echo showed HCM without significant outflow obstruction; EP study demonstrated an FVBT with inducible AF; CMR showed midventricular septal thickness of 22 mm with patchy enhancement involving 25% of myocardial mass.

CaseNotHPOs: HP:0001635; HP:0001279; HP:0001645

CaseNotHPOFreeText: No heart failure reported; no syncope; alive at publication.

CasePreviousTesting: ECG (pre-excitation), Holter (NSVT), echo (HCM without significant outflow obstruction), EP study (FVBT with inducible AF), CMR (midventricular septum 22 mm, patchy enhancement 25% of mass).

GenotypingMethod: HCMNext panel (Ambry Genetics); heterozygous c.655G>C (p.Val219Leu) in MYBPC3, reported pathogenic.

FunctionalAnalysis: None performed.

Variant: MYBPC3 NM_000256.3:c.655G>C (p.Val219Leu); heterozygous missense

ClinVar: 42784

CAID: CA015670

gnomAD: 0.00002

AdditionalInfo:N/A

Case1: Pedigree mother; affected carrier; HCM progressing to DCM; clinical case

DiseaseAssertion: Hypertrophic cardiomyopathy progressing to dilated cardiomyopathy, with pre-excitation; MYBPC3-related

FamilyInfo: Carries the familial MYBPC3 variant. ICD in place for nonischemic cardiomyopathy despite optimal medical therapy; never received a shock. Mother of the proband and the sister.

ParentalTesting: Not applicable, this is the transmitting generation.

CasePresentingHPOs: HP:0001639; HP:0001644; HP:0004308

CaseHPOFreeText: Serial echocardiography over 11 years documented progression from hypertrophic to dilated phenotype. ECG showed pre-excitation. ICD implanted; no appropriate or inappropriate therapy to date.

CaseNotHPOs: HP:0001279 ; HP:0001645

CaseNotHPOFreeText: No syncope reported; alive at publication.

CasePreviousTesting: Serial echocardiography; ECG; ICD interrogation.

Genotyping Method: Family screening; carrier status reported.

FunctionalAnalysis: None performed.

Variant: MYBPC3 NM_000256.3:c.655G>C (p.Val219Leu); heterozygous missense

ClinVar: 42784

CAID: CA015670

gnomAD: 0.00002

AdditionalInfo:N/A

Case#: Proband and family; distal arthrogryposis phenotype; clinical case

DiseaseAssertion: Distal arthrogryposis (DA); MYBPC1-related

FamilyInfo: Two MYBPC1 variants segregate in the family. The paper provides the pedigree and segregation data.

ParentalTesting: Not stated

CasePresentingHPOs: HP:0002804

CaseHPOFreeText: Distal arthrogryposis phenotype in affected family members, per the paper's clinical description.

CaseNotHPOs: Not stated

CasePreviousTesting: Clinical evaluation, genetic testing for MYBPC1.

Genotyping Method: Genetic testing confirmed MYBPC1 variants; specific method in the paper.

FunctionalAnalysis: Confirm whether a functional assay was performed.

Variant: MYBPC1, two variants, specific nucleotide changes need confirmation from the paper

ClinVar:N/A

CAID:N/A

gnomAD:N/A

AdditionalInfo: N/A

Case#:reports one patient with this variant

DiseaseAssertion: Hypertrophic cardiomyopathy (HCM)

FamilyInfo: N/A

ParentalTesting:N/A

CasePresentingHPOs: HP:0001639 "Hypertrophic cardiomyopathy"

CaseHPOFreeText: The study cohort consisted of 23 patients diagnosed with HCM.

CaseNotHPOs: N/A

CaseNotHPOFreeText:N/A

CasePreviousTesting:N/A

Genotyping Method: Sanger sequencing

FunctionalAnalysis: none preformed

Variant: MYBPC3 c.1037G>C, p.Arg346Pro

ClinVar: No exact match, closest is MYBPC3 c.1037G>A

CAID: N/A

gnomAD:N/A

AdditionalInfo: variant is suspected to be novel and potentially pathenogenic

Case2: Sex not stated, age 8 months at diagnosis, ethnicity not stated

DiseaseAssertion: Restrictive cardiomyopathy (RCM)

FamilyInfo: Patients 2 and 3, monozygotic twins, were diagnosed with RCM at the age of 8 and 13 months, respectively. No familial history of cardiac disorders was reported in the R170W case, parental testing confirmed that the R170W variant occurred de novo (however, no parental proof was performed)

ParentalTesting: Parental testing confirmed that the R170W variant occurred de novo (however, no parental proof was performed). Parents do not carry the variant

CasePresentingHPOs: HP:0001723, HP:0002875, HP:0005110

CaseHPOFreeText: Echocardiographic examination revealed a restrictive filling pattern and enlarged atria. Both children died at the age of 12 and 18 months, respectively, due to congestive heart failure and atrial fibrillation

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: Total genomic DNA was extracted from peripheral blood using FlexiGene DNA Kit (Qiagen) according to the manufacturer’s protocol. The TNNI3 gene was screened for mutations using dye terminator sequencing. In both cases additional target sequencing including a panel of 108 cardiomyopathy- and channelopathy-associated genes was performed using Illumina MiSeq as previously described

FunctionalAnalysis: Functional analysis performed on recombinant proteins. Both cTnI-R170G/W strongly enhanced the Ca2+-sensitivity of skinned fibres, as is typical for RCM-mutations. Both mutants strongly enhanced the affinity of troponin (cTn) to tropomyosin compared to wildtype cTn. The stability of reconstituted thin filaments was reduced as revealed by electron microscopy.

Variant: NM_000363.5:c.508C>T (p.Arg170Trp)

ClinVar: 179285

CAID: CA021778

gnomAD: chr19-55154071-G-A

AdditionalInfo: Monozygotic twin

Case1: Male, age 3 at diagnosis, ethnicity not stated

DiseaseAssertion: Restrictive cardiomyopathy (RCM)

FamilyInfo: Familial screening in the R170G proband documented a hypertrophic cardiomyopathy with restrictive filling pattern in patient’s father, but the family refused additional genetic testing. No other family history of cardiac disorders stated.

ParentalTesting: The family refused additional genetic testing

CasePresentingHPOs: HP:0001723, HP:0001650, HP:0001654

CaseHPOFreeText: Patient 1 showed an impaired left ventricular function and pulmonary hypertension at three years of age. Heart biopsy showed mild cardiomyocyte hypertrophy and interstitial fibrosis. He was diagnosed with RCM and died one year later of ventricular fibrillation.

CaseNotHPOs: NR

CaseNotHPOFreeText: Target sequencing including a panel of 108 cardiomyopathy- and channelopathy-associated genes revealed no additional pathogenic or likely pathogenic variants

CasePreviousTesting: Additional target sequencing including a panel of 108 cardiomyopathy- and channelopathy-associated genes was performed using Illumina MiSeq as previously described.

Genotyping Method: Total genomic DNA was extracted from peripheral blood using FlexiGene DNA Kit (Qiagen) according to the manufacturer’s protocol. The TNNI3 gene was screened for mutations using dye terminator sequencing. In both cases additional target sequencing including a panel of 108 cardiomyopathy- and channelopathy-associated genes was performed using Illumina MiSeq as previously described

FunctionalAnalysis: Functional analysis performed on recombinant proteins. Both cTnI-R170G/W strongly enhanced the Ca2+-sensitivity of skinned fibres, as is typical for RCM-mutations. Both mutants strongly enhanced the affinity of troponin (cTn) to tropomyosin compared to wildtype cTn. The stability of reconstituted thin filaments was reduced as revealed by electron microscopy.

Variant: NM_000363.5:c.508C>G (p.Arg170Gly)

ClinVar: 165517

CAID: CA021769

gnomAD: NR

AdditionalInfo: NR

Case#: II.3, 30-year-old man from an Indian family.

DiseaseAssertion: Familial hypertrophic cardiomyopathy.

FamilyInfo: Figure 1A. His father (I.1), brother (II.1), and sister (II.2) had HCM and carried TPM1 p.Gln68Arg. His mother (I.2) had a normal echocardiogram and tested negative for the variant. The authors report autosomal dominant segregation.

ParentalTesting: Father positive for TPM1 p.Gln68Arg. Mother negative.

CasePresentingHPOs: HP:0001639, HP:0001712, HP:0005144, HP:0031656, HP:0001653, HP:0010872, HP:4000004

CaseHPOFreeText: Echo showed asymmetric septal hypertrophy and trivial mitral regurgitation. The interventricular septum measured 2.1 cm and the left ventricular posterior wall measured 1.2 cm. ECG showed a left ventricular hypertrophy strain pattern with T-wave inversions in leads II, III, aVF, and V2–V6. Cardiac MRI showed patchy STIR hyperintensity and late gadolinium enhancement in the thickened septum.

CaseNotHPOs: HP:0000822 (no history of hypertension), HP:0032092 (no left ventricular outflow tract obstruction at rest)

CaseNotHPOFreeText: Asymptomatic at presentation. Both atria and the right ventricle were normal in size and function. Left ventricular ejection fraction was 63%.

CasePreviousTesting: NR (prior genetic testing details not available in the article).

Genotyping Method: Custom targeted amplicon sequencing panel of nine sarcomeric genes on the Ion Torrent PGM. Sanger sequencing confirmed the TPM1 variant.

FunctionalAnalysis: NR (functional assay results not available in the article).

Variant: NM_001018005.2(TPM1).203A>G (p.Gln68Arg), heterozygous.

ClinVar: 1490086

CAID: NR (CAID not listed in the article).

gnomAD: No variant record found in gnomAD v4.1 for 15-63044115-A-G.

AdditionalInfo: PMID 38223010. Figure 1A identifies the proband and shows the pedigree. Figures 1B–D show cardiac imaging. Figure 1E shows Sanger sequencing. Figure 1F shows conservation of the affected residue. The authors also report computational predictions of a damaging effect.

Case#: Single case; 37-year-old male construction worker; sudden unexplained death (SUD); found dead in bed ~1 hr after lunch, August 2005; molecular autopsy via WES in 2019 from autopsy tissue

DiseaseAssertion: Sudden unexplained death (SUD); no structural cardiac cause at autopsy; MYBPC3/TTN/ACADVL/RYR2-related per WES reevaluation

FamilyInfo: No family history or segregation data reported. The paper is a single molecular autopsy; no relatives were genotyped or phenotyped. No pedigree assessment performed.

ParentalTesting: Not performed, no family members tested.

CasePresentingHPOs: HP:0001698 (Sudden cardiac death); HP:0004756 (Ventricular tachycardia), the latter only as a speculative arrhythmic mechanism, not a documented clinical event

CaseHPOFreeText: Found dead in bed ~1 hr after lunch in August 2005. External examination showed no traumatic injury; toxicological blood screen negative. Clinical history unremarkable. Heart weighed 350 g (reference 331±57 g in men) with regular morphology and volume. Microscopy showed small foci of interstitial fibrosis, deemed not significant. No other organ showed significant abnormality. Case dismissed as SUD, reevaluated in 2019.

CaseNotHPOs: HP:0001639; HP:0001644; HP:0004308; HP:0001279

CaseNotHPOFreeText: No structural cardiac disease at autopsy, no hypertrophy, no dilation, normal heart morphology and volume. No evidence of any cardiomyopathy phenotype. No documented arrhythmia or syncope in life.

CasePreviousTesting: Autopsy (2005) with toxicology, histology. WES (2019) on DNA from FFPE left ventricular tissue; 562-gene cardiac panel (234 SCD/heart-disease genes + 328 heart-expressed genes); filtering against gnomAD (rare = MAF <0.1%); in silico prediction with DANN, MutationTaster, FATHMM, MutationAssessor, PolyPhen-2, SIFT, PROVEAN; ACMG 2015 classification; WebGestalt enrichment analysis.

Genotyping Method: WES on Illumina 500 (TruSeq library prep, xGen exome capture), SeqMule pipeline, ENLIS Genome Research annotation; variants confirmed by Sanger sequencing. Aligned to GRCh37.

FunctionalAnalysis: None performed by the authors, no functional assays in this paper. (ACADVL p.V383A residual activity ~20% is cited from a 2007 external study, not performed here.)

Variant: Four heterozygous missense variants, one per gene

ClinVar:926037

CAID: CA221696968

gnomAD: N/A

AdditionalInfo:N/A

Case1: Male, 24 years old at diagnosis, ethnicity not stated

DiseaseAssertion: Dilated cardiomyopathy (DCM)

FamilyInfo: Three affected family members carry the D94A mutation, mother (I.2, diagnosed age 21 with peripartum cardiomyopathy), sister (II.1, diagnosed age 29), and proband (II.2, diagnosed age 24). Sanger sequencing confirmed the MYL2 variant was present in all three affected family members (I.2, II.1, and II.2).

ParentalTesting: Mother confirmed as heterozygous carrier of D94A mutation with DCM phenotype. Father not a carrier, unaffected

CasePresentingHPOs: HP:0001644, HP:0006699

CaseHPOFreeText: The proband (II.2) and his sister (II.1) were diagnosed at ages 24 and 29 after preventive cardiovascular screening revealed mild global left ventricular systolic dysfunction. Medical therapy was initiated upon evidence of decreased ejection fraction. Patients II.1 and II.2 (proband) displayed abnormal ECG findings and systolic dysfunction as manifested by reduced EF. However, the LV and septal wall thickness were within the normal range.

CaseNotHPOs: NR

CaseNotHPOFreeText: Septal wall thickness measurements were within normal range in all affected family members. LV wall thickness within normal range.

CasePreviousTesting: No prior testing.

Genotyping Method: Twenty two variants, meeting our established criteria for exome sequencing analysis, were identified in the three affected family members of the pedigree. Exome sequencing performed; variant confirmed by Sanger sequencing. Sanger sequencing confirmed the MYL2 variant was present in all three affected family members (I.2, II.1, and II.2)

FunctionalAnalysis: Functional analysis performed on recombinant proteins, not directly on patient samples. Far-UV CD spectroscopy was used to analyze the effect of the D94A mutation on the secondary structure of the RLC. The mutation was observed to induce a reduction in the α-helical content of the RLC and imposed intra-molecular rearrangements. The mutation was seen to impair the binding of RLC to the MHC (myosin heavy chain), and its incorporation into the RLC-depleted porcine myosin. The actin-activated ATPase activity of mutant-reconstituted porcine cardiac myosin was significantly higher compared to ATPase of WT

Variant: NP_000423.2:p.Asp94Ala

ClinVar: 4710041

CAID: CA386698152

gnomAD: NR

AdditionalInfo: Three affected family members carry the variant (mother I.2, sister II.1, proband II.2)

Case1: 12 year old male

DiseaseAssertion: RCM

FamilyInfo:

ParentalTesting: Sanger sequencing was deemed healthy.

CasePresentingHPOs:HP:0012378, HP:0003546, HP:0002094, HP:0002240

CaseHPOFreeText: High BNP, enlarged atrium, ST-T segment change, left ventricular restrictive filling in Table 2.

CaseNotHPOs:

CaseNotHPOFreeText:

CasePreviousTesting: Routine blood tests, tuberculin tests, TTE, ECG, chest X-ray. MRI

Genotyping Method: Sanger sequencing

FunctionalAnalysis:

Variant: CA021957

ClinVar:

CAID:

gnomAD:

AdditionalInfo:

Case#: 31 year old man of European ancestry. Patient ID NR.

DiseaseAssertion: Nonischemic dilated cardiomyopathy.

FamilyInfo: No reported family history of dilated cardiomyopathy. Both parents had normal heart exams and echocardiograms.

ParentalTesting: Both biological parents tested negative for the TPM1 variant. Sequencing coverage was 500 to 600×. The authors thought the variant likely arose de novo. They could not rule out parental germline mosaicism.

CasePresentingHPOs: HP:0001644, HP:0025169, HP:0001635, HP:0001640, HP:0002202, HP:0002875, HP:0002094, HP:0012764, HP:0034807

CaseHPOFreeText: He first felt short of breath during activity. Later he felt short of breath at rest. He also had a persistent cough and abdominal swelling. Chest CT showed an enlarged heart and fluid around both lungs. The echo showed that both ventricles were enlarged and pumped poorly. His left ventricular ejection fraction was 12%. His heart failure worsened and he needed a heart transplant.

CaseNotHPOs: HP:4000004 (no myocardial late gadolinium enhancement on cardiac MRI).

CaseNotHPOFreeText: The biopsy and exam of the removed heart did not show evidence of active myocarditis.

CasePreviousTesting: NR

Genotyping Method: The Invitae Dilated Cardiomyopathy Panel used next generation sequencing to test 41 genes.

FunctionalAnalysis: Thin filaments with T237S needed more calcium to reach the same level of activation. At low calcium the mutant filaments were less likely to be open and myosin ATPase activity was lower. Omecamtiv mecarbil restored calcium sensitivity in the lab assay. See Figures 3 through 5 and Tables 1 and 2.

Variant: NM_001018005.2(TPM1):c.710C>G (p.Thr237Ser). Heterozygous.

ClinVar: 1067773

CAID: CA392724554

gnomAD: No variant record found in gnomAD v4.1.

AdditionalInfo: PMID 36739943. Figure 1 shows the echo and biopsy results. The clinical report called the variant a VUS. The study authors considered it likely pathogenic after lab testing.

Case1: Female, four years five months

DiseaseAssertion: RCM

FamilyInfo: “ No family history of RCM or other cardiovascular diseases was reported.”

ParentalTesting: NA

CasePresentingHPOs:HP:0002094, HP:0002875,

CaseHPOFreeText: “congestive hepatomegaly” “lower extremity edema” “increased heart shadow without calcification of the pericardium” “bi-atrial enlargement without calcification of the pericardium, thickened pericardium, or endocardium” “‘eft and right atria were enlarged, the right ventricle was slightly enlarged”

CaseNotHPOs:

CaseNotHPOFreeText: “the left ventricle was normal in size, without calcification of the pericardium, thickened pericardium, or endocardium”

CasePreviousTesting: Chest X-ray, Abdominal ultrasonography, MRI, Two-dimensional echocardiography

Genotyping Method: Sanger Sequencing

FunctionalAnalysis: NA

Variant:c.508C>T p.Arg170Trp

ClinVar: 4188245

CAID:

gnomAD:

AdditionalInfo:

Case2: Five year old female

DiseaseAssertion: RCM

FamilyInfo: “No family history of RCM or other cardiovascular diseases was reported.”

ParentalTesting:

CasePresentingHPOs:HP:0002875, HP:0002094

CaseHPOFreeText: “lower extremity edema” “congestive hepatomegaly” “ increased heart shadow without calcification of the pericardium” “bi-atrial enlargement without calcification of the pericardium, thickened pericardium, or endocardium”

CaseNotHPOs:

CaseNotHPOFreeText:

CasePreviousTesting: Abdominal ultrasonography, ECG, Chest X-ray, MRI, Two-dimensional echocardiography

Genotyping Method: Sanger Sequencing

FunctionalAnalysis:

Variant: NM_006757.4(TNNT3):c.575G>A (p.Gly192Asp)

ClinVar: 4633351

CAID:

gnomAD:

AdditionalInfo:

Case1: 38 year old male

DiseaseAssertion: . Two missense variants in MYBPC3 (NM_000256.3): c.2533C>G in exon 26 (C6 domain) were identified and, classified as a variant of uncertain significance (VUS, score 2), and c.1696T>A in exon 18 (C4 domain), a VUS with a score of 5.

FamilyInfo: There was no family history of cardiomyopathy or SCD.

ParentalTesting: NR

CasePresentingHPOs: HP:0004751, HP:0006682, HP:0001712

CaseHPOFreeText: 38 year old man, suffering from contractions, and one short run of non-sustained ventricular tachycardia lasting four beats. Asymmetric septal hypertrophy with a maximum thickness of 19 mm. In addition, marked biatrial enlargement was evident, with a left atrial volume index of 79 mL/m² and right atrial area of 25 cm². Importantly, extensive diffuse late gadolinium enhancement (LGE) was detected in the basal and mid-septal and anterior segments, involving 17% of the myocardial mass

CaseNotHPOs: NR

CasePreviousTesting: genetic testing was performed using the Health in Code HCM panel, which includes the following 18 genes: ACTC1, DES, FHL1, FHOD3, GLA, LAMP2, MYBPC3, MYH7, MYL2, MYL3, PRKAG2, PTPN11, TNNC1, TNNI3, TNNT2, TPM1, TRIM63, and TTR.

Genotyping Method: Health in Code HCM panel

FunctionalAnalysis:

Variant: NM_000256.3:c.2533C>G, NM_000256.3:c.1696T>A

ClinVarID:180973, 915724

CAID:CA380324353, CA012504

gnomAD:

AdditionalInfo:NR

Case1: 50‐year‐old woman

DiseaseAssertion: Ankles swelling and shortness of breath.

FamilyInfo: NR

ParentalTesting: NR

CasePresentingHPOs:

CaseHPOFreeText: dilated cardiomyopathy with end‐diastolic diameter of the left ventricle (LV) of 62 mm, severely depressed left ventricle ejection fraction (LVEF), 20%, mild hypertrophic septum (13.5 mm), trabecular aspect of lateral and inferior LV wall, thrombus in the apex, and severe tricuspid regurgitation with inferior vena cava reflow

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: next‐generation sequencing

FunctionalAnalysis: NR

Variant: NM_000256.3(MYBPC3):c.2459G>A (p.Arg820Gln), NM_032578.4(MYPN):c.3335C>T (p.Pro1112Leu)

ClinVar: 8617, 31791

CAID: CA012326, CA143763

gnomAD: 11-47359085-C-T, 10-69959174-C-T

AdditionalInfo: NR

Case#: a male in the age range of 36-40

DiseaseAssertion: Dilated cardiomyopathy and generated hiPSC-CMS

FamilyInfo: not reported

ParentalTesting: not reported

CasePresentingHPOs: HP:0002875, HP:0031352 Exertional dyspnea and chest tightness

CaseHPOFreeText: nocturnal dyspnea and reduced exercise tolerance

CaseNotHPOs:

CaseNotHPOFreeText:

CasePreviousTesting: echocardiogram and electrocardiograms

Genotyping Method: peripheral blood was extracted and use to sequence the entire genome

FunctionalAnalysis: hiPSCs were looked at in this case

Variant: NM_000256.3: c.194 C > T (p.Thr65Met)

ClinVar:407324

CAID: CA047700

gnomAD: 11-47372888-G-A

AdditionalInfo:F

Case#: Female with DCM symptoms beginning at age 30

DiseaseAssertion: Dilated cardiomyopathy (DCM) associated with a heterozygous missense variant in MYBPC3, c.3373G>A (p.Val1125Met). The authors propose autosomal dominant inheritance in this DCM case.

FamilyInfo: NR – Detailed family relationships, segregation testing, and individual relatives' phenotypes are not described for the current DCM proband.

ParentalTesting: NR

CasePresentingHPOs: HP:0001644 (Dilated cardiomyopathy); HP:0002094 (Dyspnea); HP:0001962 (Palpitations); HP:0004756 (Ventricular tachycardia)

CaseHPOFreeText: The patient experienced symptoms beginning at age 30, including frequent palpitations and dyspnea. ECG monitoring revealed multiple premature ventricular contractions and nonsustained ventricular tachycardia. Echocardiography demonstrated severe spherical left ventricular enlargement, severe systolic and diastolic dysfunction, LVEF of 10%, and mild pulmonary hypertension. She was classified as NYHA functional class II–III and received medical therapy and an implantable cardioverter-defibrillator.

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR – Article describes patient's clinical evaluation, including ECG monitoring and echocardiography, before genetic analysis.

Genotyping Method: Genomic DNA was extracted from peripheral blood. Targeted next-generation sequencing was performed using a custom NimbleGen panel covering the coding regions and exon–intron boundaries of 23 genes associated with DCM. Sequencing was conducted on an Illumina HiSeq 2000 platform. Reads were aligned to the hg19 reference genome using BWA, and SAMtools was used for variant analysis. MYBPC3 variant confirmed using Sanger sequencing.

FunctionalAnalysis: In silico analyses were performed to investigate the potential functional consequences of MYBPC3 p.Val1125Met. SIFT, PolyPhen-2, and MutationTaster predicted potentially damaging effects, while CADD produced a score of 33. Multiple-sequence alignment demonstrated that Val1125 is highly conserved across species. Protein modeling using I-TASSER and Phyre2 predicted structural differences involving the region surrounding residue 1125, located within the C9 fibronectin type III domain of cardiac myosin-binding protein C (cMyBP-C). The authors proposed that the substitution could affect protein structure and function. No direct experimental functional validation of this variant was reported.

Variant: MYBPC3 NM_000256.3:c. 3373G>A (p.Val1125Met); rsID: rs121909378; missense; heterozygous

ClinVar: 8604

CAID: CA014038

gnomAD: MYBPC3 c.3373G>A (p.Val1125Met), GRCh38: 11-47332931-C-T. In gnomAD v4, the reported allele frequencies are 0.00001920 (exomes), 0.00003943 (genomes), and 0.00002111 (total). The highest ancestry-specific allele frequency identified was in the Ashkenazi Jewish population (AC = 5; AF = 0.0001695).

AdditionalInfo: Authors propose variant dosage, interactions with other variants, and genetic modifiers may contribute to differences in disease phenotype. However, the proposed autosomal dominant association with DCM was not supported by documented segregation testing in the current proband's family, and the functional analyses were computational rather than experimental.

Case#: AD-FDC27, II:11, male, age 35

DiseaseAssertion: Familial dilated cardiomyopathy

FamilyInfo: second multigenerational DCM family

CasePresentingHPOs: HP:0001644 HP:4000141

CaseHPOFreeText: Dyspnea on exertion; left ventricular dilation; severe systolic dysfunction

Genotyping Method: Whole-exome sequencing using Agilent SureSelect 50 Mb exome; HiSeq 2000 sequencing followed by Sanger sequencing confirmation

Variant: TNNT2 c.517C>T (p.Arg173Trp); missense single-nucleotide variant; heterozygous

ClinVar: 228409; Pathogenic

CAID: CA10576372

Case#: AD-FDC1, IV:14, male, age 45

DiseaseAssertion: Familial dilated cardiomyopathy

FamilyInfo: multigenerational DCM family

CasePresentingHPOs: HP:0001644 HP:4000141 HP:0012664

Genotyping Method: Whole-exome sequencing using Agilent SureSelect 50 Mb exome; HiSeq 2000 sequencing followed by Sanger sequencing confirmation

Variant: TNNT2 c.517C>T (p.Arg173Trp); missense single-nucleotide variant; heterozygous

ClinVar: 228409

CAID: CA10576372

Case#: 38 year old woman

DiseaseAssertion: Hypertrophic cardiomyopathy (HCM)

FamilyInfo: Father and one brother had HCM, no sudden deaths reported in family

ParentalTesting: Father carried the same heterozygous variant

CasePresentingHPOs: HP:0001962, HP:0031352 “palpitation and chest distress”

CaseHPOFreeText: myocardial fibrosis

CaseNotHPOs: N/A

CaseNotHPOFreeText: Unremarkable

CasePreviousTesting: N/A

Genotyping Method:PCR

FunctionalAnalysis: N/A

Variant: TNNI3 heterozygous c.235C>T (p.Arg79Cys)

ClinVar: Variation ID: 43367

CAID:N/A

gnomAD:N/A

AdditionalInfo: authors describe the variant as novel

Case#:27-year-old woman

DiseaseAssertion: Familial restrictive cardiomyopathy (RCM)

FamilyInfo: Strong family history of cardiac disease and sudden cardiac death

ParentalTesting:N/A

CasePresentingHPOs: “ Fatigue, dyspnoea , palpitations, atrial fibrillation, pulmonary hypertension, and fluid congestion.”

CaseHPOFreeText: age 27, she presented with progressive fatigue and limited exercise capacity, 13-year symptom-free interval, she developed rapid clinical deterioration with dyspnoea and palpitations

CaseNotHPOs: N/A

CaseNotHPOFreeText: N/A

CasePreviousTesting: focused screening of MYH7, TNNT2, and MYBPC3 was unremarkable,

Genotyping Method: NGS

FunctionalAnalysis:N/A

Variant: TNNI3, NP_000354.4: p.Lys193Glu; NC_000019.9: g.55663258T>C. Heterozygous reported as novel

ClinVar: N/A

CAID:N/A

gnomAD: N/A

AdditionalInfo: patient improved with restored sinus rhythm and low-dose diuretic treatment and was symptom-free at the time of reporting. later had an ischaemic stroke

Case#:7 ¾ year old girl

DiseaseAssertion: Hypertrophic cardiomyopathy (HCM), with ventricular tachycardia and Stokes–Adams syndrome.

FamilyInfo: Parents not consanguineous, no family history of cardiovascular disease or sudden cardiac death.

ParentalTesting: Parents not consanguineous, no symptoms

CasePresentingHPOs: HP:0001639, HP:0001695, HP:0001663, HP:0001250, HP:0001678, HP:0001712 “Hypertrophic cardiomyopathy, cardiac arrest, ventricular tachycardia, seizures, atrioventricular block, left ventricular hypertrophy:”

CaseHPOFreeText: Diagnosed with cardiomyopathy in utero. Frequent cardiac arrests from 3-7, multiple seizures a year, cardiac mri showed heart enlargement, hypertrophy, after icd implant no cardiac arrests after 1 year.

CaseNotHPOs: N/A

CaseNotHPOFreeText: N/A

CasePreviousTesting: diagnosed with cardiomyopathy in utero, no other testing stated.

Genotyping Method: Whole exon sequencing

FunctionalAnalysis: protein modeling only, revealed to be “probably damaging” score 1.0

Variant: MYH7 NM_000257.3:c.2723T>C (p.Leu908Pro; p.L908P)

ClinVar: no id but is listed under https://www.ncbi.nlm.nih.gov/clinvar/RCV000158849.1/?cmd=HTOn&utm_source=chatgpt.com

CAID: N/A

gnomAD:N/A

AdditionalInfo: patient underwent ICD implantation and had no further arrests after a years time.

Case#: P2 female; age 2 years; Vietnamese family

DiseaseAssertion: Dilated cardiomyopathy

FamilyInfo: MYL2 variant was reported as de novo in P2

ParentalTesting: Sanger sequencing of family members; variant was absent in the parents

CasePresentingHPOs: HP:0001644 HP:0012664 HP:4000141

CaseHPOFreeText: Dilated cardiomyopathy; reduced ejection fraction of 30%; increased diastolic cardiac diameter of 37 mm

Genotyping Method: Whole-exome sequencing using the SureSelect Human All Exon V7 kit, followed; Sanger sequencing confirmation

Variant: MYL2 c.284C>G, p.Pro95Arg; heterozygous missense variant

Case#: Family A, Case III.7; 38-year-old female; diagnosed at age 26

DiseaseAssertion: Hypertrophic cardiomyopathy (HCM)

FamilyInfo: Positive family history of HCM and SCD. Mother (II.4), brother (III.8), uncle (II.7), and cousin (III.11) died of SCD at ages 55, 26, 57, and 24, respectively. The proband's three children (IV.3, IV.4, IV.5) were homozygous for the MYL3 variant but had normal echocardiograms at ages 18, 13, and 6.

ParentalTesting: Supplementary Table S2 reports parental testing supportive of PM3 (variants in trans). However, DNA was unavailable for the proband's deceased mother (II.4), and individual parental genotypes were not specified in the supplementary genetic findings.

CasePresentingHPOs: HP:0001639 (Hypertrophic cardiomyopathy); HP:0002094 (Dyspnea); HP:0001653 (Mitral regurgitation); HP:0001712 (Left ventricular hypertrophy)

CaseHPOFreeText: HCM diagnosed at age 26 following dyspnea. At age 38, echocardiography showed reverse-curvature HCM with asymmetric left ventricular hypertrophy involving anterior, anterolateral, and lateral segments; maximum wall thickness 22 mm; severe mitral regurgitation; LVEF 55%; E/e' ratio 16.4; resting LVOT gradient 9 and post-maneuver gradient 30. Holter monitoring showed no arrhythmias (Supplementary Results, pp. 5–6; Table S1; Fig. S1).

CaseNotHPOs: HP:0001324 (Muscle weakness)

CaseNotHPOFreeText: Neurological evaluation revealed normal muscle tone, strength 5/5 in upper and lower limbs, no distal or proximal muscle atrophy or fasciculations, and normal creatine phosphokinase levels.

CasePreviousTesting: Exome sequencing was performed; no rare, likely pathogenic variants in other cardiomyopathy-associated genes identified after filtering.

Genotyping Method: Exome sequencing identified the MYL3 variant; bidirectional Sanger sequencing validated the variant. Familial genotyping supported recessive inheritance (Fig. 1a).

FunctionalAnalysis: Zebrafish cmlc1 knockdown and rescue experiments were performed using human MYL3 RNA carrying c.170C>A (p.Ala57Asp). Mutant RNA showed partial phenotypic rescue but no statistically significant improvement in ventricular contractility compared with knockdown alone (Fig. 2a-d).

Variant: MYL3 NM_000258.2:c.170C>A (p.Ala57Asp); homozygous missense variant; rs139794067

ClinVar: 43121

CAID: CA013575

gnomAD: Allele frequency 0.000163 (0 homozygotes), as reported in Supplementary Table S2.

AdditionalInfo: Family A, Case III.7. Clinical characteristics and genetic findings described in the Results section (Fig. 1a and 1d-e). Functional experiments described in Fig. 2. The authors classified c.170C>A as a variant of uncertain significance (VUS).

Case#: Jenni a 7 year-old female

DiseaseAssertion: Dilated cardiomyopathy with LVNC

FamilyInfo: MYH7 maternally inherited and MYBPC3 paternally inherited

ParentalTesting: Mother has PPCM

CasePresentingHPOs: HP:0004755

heart failure and supraventicular tachycardia

CaseHPOFreeText: Intermittent Wolff-Parkinson- White

CaseNotHPOs:

CaseNotHPOFreeText:

CasePreviousTesting: Echocardiogram and MRI

Genotyping Method: Segregation analysis, targeted next generation sequencing

FunctionalAnalysis: electrophysiology, transplant evaluation, CT angiography

Variant: NM_000256.3(MYBPC3):c.2672G>A (p.Arg891Gln)

ClinVar:177884

CAID: CA012826

gnomAD: 11-47357493-C-T

AdditionalInfo:

Case#: Patient 1, individual II.1 (Fig. 2A); 22-year-old Salvadoran female

DiseaseAssertion: Restrictive cardiomyopathy (RCM) with advanced heart failure

FamilyInfo: Patient denied a family history of cardiomyopathy, although supporting records were unavailable. Her mother (I.2) was clinically unaffected at age 45 and heterozygous for both MYL3 p.Glu143Lys and MYL2 p.Gly57Glu. Other family members were unavailable for evaluation (Fig. 2A; Table I).

ParentalTesting: Mother (I.2) was confirmed heterozygous for MYL3 c.427G>A (p.Glu143Lys) and MYL2 c.170G>A (p.Gly57Glu). Paternal testing was not reported.

CasePresentingHPOs: HP:0012764 (Orthopnea); HP:0004749 (Atrial flutter); HP:0031295 (Left atrial enlargement); HP:0030718 (right atrial enlargement)

CaseHPOFreeText: Worsening fatigue and exertional dyspnea over 12 months, paroxysmal nocturnal dyspnea, palpitations, NYHA Class III–IV heart failure, and ascites suggestive of congestive hepatopathy. Echocardiography showed severe biatrial enlargement and advanced left ventricular diastolic dysfunction with preserved systolic function. Additional findings included myocardial fibrosis and myofiber disarray on biopsy.

CaseNotHPOs: NR

CaseNotHPOFreeText: At initial presentation, patient denied dizziness, syncope, and lower-extremity edema. No S4 heart sound was detected. Recurrent syncope developed later.

CasePreviousTesting: Targeted sequencing of eight sarcomere genes (ACTC, MYBPC3, MYH7, MYL2, MYL3, TNNI3, TNNT2, TPM1). Genome-wide analysis was not reported. An additional heterozygous MYL2 variant, c.170G>A (p.Gly57Glu), was identified (ClinVar Variation ID: 43458; CAID: CA009910).

Genotyping Method: Sequencing of coding exons and intron–exon boundaries of MYL3 and seven additional sarcomere genes, performed by a commercial CLIA-certified laboratory (Correlagen Diagnostics, Inc.). The specific sequencing platform was not reported.

FunctionalAnalysis: NR

Variant: MYL3 NM_000258.2:c.427G>A (p.Glu143Lys); homozygous

ClinVar: 14063

CAID: CA013774

gnomAD: MYL3 c.427G>A (p.Glu143Lys). Highest reported ancestry-specific allele frequency: 0.0002333 (0.02333%) in the Admixed American population (AC = 14). Overall AF (exomes): 0.000008209; AF (genomes): 0.00001314; AF (total): 0.000008674. https://gnomad.broadinstitute.org/variant/3-46859529-C-T?dataset=gnomad_r4.

AdditionalInfo: Patient developed recurrent syncope and received an implantable cardioverter-defibrillator. She underwent orthotopic heart transplantation six months after RCM diagnosis. Authors considered the homozygous MYL3 and heterozygous MYL2 variants likely contributors to disease, although their individual contributions were not established. Clinical and family findings are reported in Patient 1, Figure 2A, and Table I.

Case#: a 2‐year‐old white girl who was found to have RCM following an evaluation precipitated by the sudden death of her older brother.

DiseaseAssertion: Restrictive cardiomyopathy

FamilyInfo: 4‐year‐old brother presented with a sudden cardiac arrest while running on a soccer field and could not be resuscitated. Her father had restrictive physiology and arrhythmias. The TNNT2 variant was found in the father and two children

ParentalTesting: Father carried the variant. For both paternal grandparents tested negative and the proband inherited the variant from her father.

CasePresentingHPOs: HP:0001723, HP:0001639, HP:0031295, HP:0030718, HP:0001695

CaseHPOFreeText: "Her ECG demonstrated criteria for right and left atrial enlargement with marked repolarization abnormality. Echocardiogram revealed mild right atrial and severe left atrial enlargement (left atrial volume, 61.5 cc/m2; normal, 16–28), with mildly increased left ventricular mass and otherwise normal ventricular dimensions. Right and left ventricular systolic function was preserved. "

CaseNotHPOs: not reported

CaseNotHPOFreeText: Ventricular dimensions and biventricular systolic function were reported as normal.

CasePreviousTesting: Cardiomyopathy‐based panel testing (Familion; Transgenomic, Inc., New Haven, CT) was conducted on the proband, demonstrating a single, heterozygous, variant TNNT2‐R94C (c.280C>T).

Genotyping Method: Clinical genetic testing was performed on family members using the same HCM panel test.

FunctionalAnalysis: Biophysical experiments using recombinant human TNNT2‐R94C demonstrated impaired cardiac regulation at the molecular level attributed to reduced calcium‐dependent blocking of myosin's interaction with the thin filament.

Variant: c.835C>T, p.Gln279Ter

ClinVar: 165549

CAID: CA004288

gnomAD: not reported

AdditionalInfo: not reported

Case#: Female, 6, non-Hispanic white

DiseaseAssertion: Dilated Cardiomyopathy

FamilyInfo: Father and Paternal uncle diagnosed with DCM at age 34.

ParentalTesting: Her father underwent cardiac screening based on family history several years later at age 34

CasePresentingHPOs: HP:0001640

CaseHPOFreeText: NA

CaseNotHPOs: NA

CaseNotHPOFreeText: Acute viral illness and gastroenteritis

CasePreviousTesting: NR

Genotyping Method: Sanger Sequencing

FunctionalAnalysis: NR

Variant: NM_001276345.2:c.149A>G

ClinVar: 2005620

CAID: CA344207232

gnomAD: 1:201337304 T / C

AdditionalInfo: NA

Case#: Male, 65

DiseaseAssertion: Idiopathic dilated cardiomyopathy

FamilyInfo:None of his five siblings were affected

ParentalTesting: NR

CasePresentingHPOs: HP:0005110

CaseHPOFreeText: Slow progression to severe heart failure

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: Bidirectional dna sequencing

FunctionalAnalysis: NR

Variant: NM_001276345.2:c.869A>G

ClinVar: 4881578

CAID: CA344201883

gnomAD: NA

AdditionalInfo: HTX. The index patient carried a known TNNT2 K247R mutation as well as two novel intronic variants in MYH7 (IVS39+7C>A) and MYBPC3 (IVS25+13T>A).

Case5: 65 year-old male

DiseaseAssertion: carried a known TNNT2 K247R mutation as well as two novel intronic variants in MYH7 (IVS39+7C>A) and MYBPC3 (IVS25+13T>A)

FamilyInfo: None of his five siblings were affected, judged by their clinical presentation, nor was there any history of cardiac disease or sudden death in the family.

ParentalTesting:NR

CasePresentingHPOs:HP:0003677, HP:0012828, HP:0001635, HP:0005110, HP:0034307, HP:0012666,

CaseHPOFreeText: had late-onset at age 47 IDC, with a slow progression to severe heart failure and subsequently HTX. He also suffered from atrial fibrillation in the later stages of his disease. Had left ventricular end diastolic diameter (in mm and indexed by body surface area (cm/m2)) with a value of 68mm and 3.4cm/m2. As well with 30% of left ventricular ejection fraction. His ECG is normal, clinical status is heart transplantation from the age of 56. CAG is normal.

CaseNotHPOs:NR

CaseNotHPOFreeText:NR

CasePreviousTesting:NR

Genotyping Method:Genetically screened, also using GenBank with PCR by amplifying the coding region

FunctionalAnalysis: The variant could thus possibly result in the synthesis of a limited amount of the slightly modified β-myosin. The functional significance of this is not easily established, but it suggests that the variant may be a disease modifier.

Variant:NM_001276345.2:c.869A>G

ClinVar:4881578

CAID:CA344201883

gnomAD:NR

AdditionalInfo: MYH7 (IVS39+7C>A) increased the likelihood of a cryptic donor splice site to 70%, possibly resulting in the synthesis of mRNA coding for a β-myosin with a C terminus of –VGLE instead of –GLNEE. As the variant is located in the last exon, the faulty spliced mRNA is probably not degraded but results in the synthesis of a modified protein.

Case 7: 47 year old male

DiseaseAssertion: novel MYH7 R1832C in the index case

FamilyInfo:His father died at the age of 47 years due to IDC, whereas a sibling of the index case died suddenly within her first year. It was not possible to obtain DNA from the deceased relatives.

ParentalTesting:NR

CasePresentingHPOs:HP:0012828,HP:0012835, HP:0034307, HP:0012666

CaseHPOFreeText: He had an early onset of symptoms, in his third decade as being the age of 33, with severe dilatation of his left ventricle and depressed LVEF, and required HTX 3 years after the onset of symptoms. A left ventricular end diastolic diameter (in mm and indexed by body surface area (cm/m2)); value of 86mm and 3.2cm/m2. Has a left ventricular ejection fraction of 20%. His clinical status is heart transplantation.

CaseNotHPOs:NR

CaseNotHPOFreeText:NR

CasePreviousTesting:NR

Genotyping Method:NR

FunctionalAnalysis:NR

Variant:NM_000257.4:c.5494C>T

ClinVar:161322

CAID:CA016134

gnomAD: gnomAD v2: 14:23884269 G / A gnomAD v3: 14:23415060 G / A gnomAD v4: chr14-23415060-G-A

AdditionalInfo: This mutation is located in the rod portion of MYH7 and replaces a basic arginine residue with a reactive neutral cysteine residue in the g-position of the heptad repeat in the α-helical myosin rod, and thus may destabilize the salt bridges required for myosin–myosin dimerization.

Case8: 56 year old male

DiseaseAssertion: A double heterozygous for the known MYBPC3 R326Q mutation.

FamilyInfo: His father died due to IDC in his fourth decade, whereas his brother developed IDC. DNA was not available from either of these individuals.

ParentalTesting:NR

CasePresentingHPOs:HP:0005110, HP:0034307,HP:0012666, HP:0011675, HP:0005110, HP:0100651

CaseHPOFreeText: He also developed atrial fibrillation, well regulated on medication. Had onset conditions at age 36. He had left ventricular end diastolic diameter (in mm and indexed by body surface area (cm/m2)); as a value of 65mm and 3.2 cm/m2. A LVEF, left ventricular ejection fraction as 15%. Arrhythmia level as atrial fibrillation. Clinical status as heart transplantation. He also has type 1 diabetes mellitus

CaseNotHPOs:NR

CaseNotHPOFreeText:NR

CasePreviousTesting:NR

Genotyping Method:NR

FunctionalAnalysis:NR

Variant:NM_000256.3:c.977G>A

ClinVar:42813

CAID:CA016212

gnomAD:gnomAD v2: 11:47367871 C / T gnomAD v3: 11:47346320 C / T gnomAD v4: chr11-47346320-C-T

AdditionalInfo:NR

Case1: A 68-year-old female

DiseaseAssertion: dilated cardiomyopathy (DCM), with the MYH7 p.Lys637Glu (K637E) variant identified in the affected patient. The study investigated sarcomeric gene variants associated with DCM

FamilyInfo: The proband's father (M1, II:3) died suddenly at 36 years of age, 2 years after being diagnosed with DCM.

ParentalTesting: Yes from father

CasePresentingHPOs: HP:0011664, HP:0011713, HP:0003677, HP:0001635,

CaseHPOFreeText: was diagnosed as having left ventricular non-compaction (LVNC) based on echocardiography. A left bundle branch block on her ECG. Echocardiography revealed LVNC and she has had a slow progression towards heart failure and an increasing dilatation of her left ventricle. Age 48 at onset, left ventricular end diastolic diameter 59 mm, left ventricular ejection fraction 25%, ventricular extrasystoles for arrhythmia.

CaseNotHPOs:NR

CaseNotHPOFreeText:NR

CasePreviousTesting:NR

Genotyping Method: genetically screened, also using GenBank with PCR by amplifying the coding region

FunctionalAnalysis:NR

Variant: NM_000257.4:c.1909A>G

ClinVar: 1329402

CAID:CA389049558

gnomAD: NR

AdditionalInfo: NR

Case 3: A 64 year old female

DiseaseAssertion: The case carried the novel MYH7 K637E mutation

FamilyInfo: Her mother died of a suspected but unconfirmed cardiac cause; thus, this was regarded as a non-FDC case. Two healthy sisters declined participation in the study.

ParentalTesting:NR

CasePresentingHPOs: HP:0003674, HP:0034307, HP:0002372, HP:0011675, HP:0005110

CaseHPOFreeText: Slowly from onset of symptoms at the age of 42 years, and received HTX in her sixth decade. Has left ventricular end diastolic diameter (in mm and indexed by body surface area (cm/m2)), 81mm and then 4.2m2. LVEF as 15%, ECG as normal. Arrhythmia as atrial fibrillation. NYHA as 4. Clinical status as heart transplantation. CAG has a normal level.

CaseNotHPOs:NR

CaseNotHPOFreeText:NR

CasePreviousTesting:NR

Genotyping Method: Genetically screened, also using GenBank with PCR by amplifying the coding region

FunctionalAnalysis: NR

Variant:NM_000257.4:c.1909A>G

ClinVar:1329402

CAID:CA389049558

gnomAD:NR

AdditionalInfo:NR

Case#:7-year-old boy

DiseaseAssertion: restrictive cardiomyopathy

FamilyInfo: his parents were in generally good health and other family members denied a history of syncope, sudden death or cardiomyopathy

ParentalTesting: sanger sequencing

CasePresentingHPOs:HP:0007185, HP:0001695, HP:0005943, HP:0002516, HP:0001663

CaseHPOFreeText:electrocardiogram (ECG) revealed Ptf-V 1 < –0.04 mm⋅s and biphasic P waves, indicating left atrial enlargement and the chest X-ray revealed an enlarged heart shadow. The echocardiogram showed biatrial enlargement, especially in the left atrium (LA: 32 mm, RA: 30 mm), decreased diastolic function (E/A = 2.6; E Peak deceleration time 130 ms; Constant volume diastolic time 49 ms), moderate mitral valve regurgitation and left ventricular ejection fraction of 51.8%.

CaseNotHPOs:HP:0000969

CaseNotHPOFreeText:Except for bilateral enlargement, cardiac magnetic resonance (CMR) indicated no abnormalities

CasePreviousTesting: brain MRI, video electrocephalogram, electrocardiogram

Genotyping Method: sanger sequencing

FunctionalAnalysis:

Variant: TNNI3 c.611(exon8)G>A,p.R204H

ClinVar:177679

CAID:CA022060

gnomAD:chr19-55151856-C-T

Case#: Female, 20, non-Hispanic white

DiseaseAssertion: Peripartum cardiomyopathy

FamilyInfo: NR

ParentalTesting: NR

CasePresentingHPOs: HP:0034807, HP:0001640

CaseHPOFreeText: NA

CaseNotHPOs: NA

CaseNotHPOFreeText: NA

CasePreviousTesting: NR

Genotyping Method: Sanger sequencing

FunctionalAnalysis: demonstrated decreased calcium sensitivity, which indicated that this mutation was likely to be disease causing

Variant: NM_001276345.2:c.505C>G

ClinVar: 2953222

CAID: CA344204620

gnomAD: NR

AdditionalInfo: PPCM was diagnosed one week postpartum.

Case#: 15

DiseaseAssertion: Dilated cardiomyopathy

FamilyInfo: NR

ParentalTesting: NR

CasePresentingHPOs: NA

CaseHPOFreeText: decreased cardiac contractility

CaseNotHPOs: NA

CaseNotHPOFreeText: NA

CasePreviousTesting: NR

Genotyping Method: Sanger sequencing

FunctionalAnalysis: NR

Variant: NM_001276345.2:c.577C>T

ClinVar: 834548

CAID: CA088264

gnomAD: NR

AdditionalInfo: NA

Case#: a 20-year-old, female, adopted Indian patient with over 662 Mb regions of homozy-gosity who presented with intellectual disability, ataxia, schizophrenia, retinal dystrophy, moder-ate-to-severe progressive sensorineural hearing loss (SNHL), congenital hypothyroidism, cleft mi-tral valve with mild mitral valve regurgitation, and dysmorphic features.

DiseaseAssertion: a cleft mitral valve with mild regurgitation

FamilyInfo: adopted

ParentalTesting: not reported

CasePresentingHPOs: HP:0001249, HP:0001251, HP:0100753, HP:0000556, HP:0000407, HP:0000851, HP:0001633, HP:0001653

CaseHPOFreeText: cleft mitral valve and dysmorphic features

CaseNotHPOs: HP:0001638

CaseNotHPOFreeText: echocardiograms at 18 were normal

CasePreviousTesting: genetic testing, including targeted panel analysis, exome sequencing on a clinical basis, and a research-based review of her raw clinical exome data, led to identifying at least three causal gene disorders to explain distinct aspects of her complex phenotype.

Genotyping Method: Genome-wide single-nucleotide polymorphism (SNP) microarray analysis was clinically performed, with no pathogenic deletions or duplications detected.

FunctionalAnalysis: not reported

Variant: NM_001001430.2:c.68-1592

ClinVar: not reported

CAID: CA032911

gnomAD: total allele frequency: 0.00004522

AdditionalInfo: n/r

Case#: A 2-year-old girl with dilated cardiomyopathy (DCM) and left ventricular noncompaction, who received a heart transplant at 26 months.

DiseaseAssertion: DCM with left ventricular noncompaction

FamilyInfo: Family history revealed that three of the father’s (A.II.2) sisters (A.II.4-A.II.6) died in infancy due to cardiac failure.

ParentalTesting: The father and paternal grandmother tested positive for the same TNNT2 variant

CasePresentingHPOs: HP:0001644, HP:0030682, HP:0001635

CaseHPOFreeText: The heart failure signs began at 2 months and got worse. Then got a heart transplant at 26 months.

CaseNotHPOs: not reported

CaseNotHPOFreeText: nothing found

CasePreviousTesting: a genetic panel test, including the genes LDB3, LMNA, MYH7, MYBPC3, and TNNT2, was performed.

Genotyping Method: Variants were confirmed in first-degree family members by Sanger sequencing.

FunctionalAnalysis: not reported

Variant: c.316G>A (p.Glu106Lys)

ClinVar: 224775

CAID: CA088557

gnomAD: not reported

AdditionalInfo: not reported

Case#: 19-year-old boy with coarctation of the aorta who complained of mild exertional dyspnea.

DiseaseAssertion: dilated cardiomyopathy (DCMP). LV systolic dysfunction.

FamilyInfo: The family history was positive to sudden death (his cousin died, aged 3 months) and to DCMP and heart transplant (HT): a maternal aunt and her son who then died at 42 and 24 years old. Cascade family screening revealed a TNNT2 variant in the mother (II.1) and his cousin (IV.3).

ParentalTesting: The 19 year old brother's was tested and carried the TNNT2 variant. She was also affected by DCM. The father’s testing status was not reported.

CasePresentingHPOs: HP:0001680, HP:0002875, HP:0025169, HP:4000141

CaseHPOFreeText: surgically repaired coarctation of the aorta who complained of mild exertional dyspnea repaired at birth (NYHA class II–III). Cardiac MRI showed a moderately dilated, hypokinetic LV with an ejection fraction of 45%; echocardiography showed an ejection fraction around 42%.

CaseNotHPOs: not reported

CaseNotHPOFreeText: Nothing was found that was correlated.

CasePreviousTesting: genetic investigations through next generation sequencing (NGS) with a panel of 325 genes, known to be associated with cardiomyopathies

Genotyping Method: targeted next generation sequencing

FunctionalAnalysis: not reported

Variant: c.518G>A (p. Arg173Gln)

ClinVar: 43649

CAID: CA004727

gnomAD: not reported

AdditionalInfo: not reported

Case#: 1. Patient II-4 43 years

DiseaseAssertion: Hypertrophic cardiomyopathy and left ventricular noncompaction

FamilyInfo: Several family members have heart disease. One relative died from cardiac arrest at age 50.

ParentalTesting: NR

CasePresentingHPOs: NR

CaseHPOFreeText: The patient had thickened heart muscle, abnormal heartbeats, and extra ridges and deep spaces in the heart muscle.

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: ECG, heart monitoring, heart ultrasound, and genetic testing

Genotyping Method: Next- generation sequencing and sanger sequencing

FunctionalAnalysis: computer testing suggested the ACTC1 gene change could weaken the protein

Variant: NM_005159.4:c.62C>T

Clinvar: 410264

CAID: CA16614451

gnomAD: NR

AdditionalInfo: His heart pumping ability was 55%. This article reported changes in his heart muscle cells.

Case#: 2 Patient II-5 46 years old

DiseaseAssertion: HCM and LVNC

FamilyInfo: Several family members have heart disease. One relative died from cardiac arrest at age 50.

ParentalTesting: NR

CasePresentingHPOs: NR

CaseHPOFreeText: The patient had thickened and enlarged heart muscle, abnormal heartbeats, and deep spaces in his heart muscle. He als had temporary episodes of reduced blood flow to the brain.

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: ECG, heart monitoring, heart ultrasound, heart MRI, heart biopsy and genetic testing

Genotyping Method: NGS and sanger sequencing

FunctionalAnalysis:computer testing suggested the ACTC1 gene change could weaken the protein.

Variant: NM_005159.4:c.62C>T

Clinvar: 410264

CAID: CA16614451

gnomAD: NR

AdditionalInfo: His heart pumping ability was 30%. He received a defibrillator and was considered for a heat transplant. He also had a second gene change in TTN.

Case#: 3 Patient II-1 10 years

DiseaseAssertion: left ventricular noncompaction

FamilyInfo: Several family members have heart disease. One relative died from cardiac arrest at age 50.

ParentalTesting: NR

CasePresentingHPOs: NR

CaseHPOFreeText: The patient had extra ridges and deep spaces in his heart muscle. His ECG also showed changes in his heart's electrical activity.

CaseNotHPOs: NR

CaseNotHPOFreeText: Normal heart muscle thickness and normal heart pumping ability.

CasePreviousTesting: ECG, heart monitoring, heart ultrasound, heart biopsy and genetic testing

Genotyping Method: NGS and sanger sequencing

FunctionalAnalysis:computer testing suggested the ACTC1 gene change could weaken the protein.

Variant: NM_005159.4:c.62C>T

Clinvar: 410264

CAID: CA16614451

gnomAD: NR

AdditionalInfo: His heart pumping ability was 63%.He received medication and remained stable during follow up.

Case#: 4 Patient III-2 14 years

DiseaseAssertion: HCM and LVNC

FamilyInfo: Several family members have heart disease. One relative died from cardiac arrest at age 50.

ParentalTesting: NR

CasePresentingHPOs: NR

CaseHPOFreeText: The patient had thickened heart muscle extra ridges and deep spaces in his heart, and episodes of fast or abnormal hearbeats.

CaseNotHPOs: NR

CaseNotHPOFreeText: Heart MRI did not show sign of heart muscle scarring

CasePreviousTesting: ECG, heart monitoring, heart ultrasound, heart biopsy and genetic testing

Genotyping Method: NGS and sanger sequencing

FunctionalAnalysis:computer testing suggested the ACTC1 gene change could weaken the protein.

Variant: NM_005159.4:c.62C>T

Clinvar: 410264

CAID: CA16614451

gnomAD: NR

AdditionalInfo: His heart pumping ability was 60%.He received medication and remained stable during follow up.

Case#:male, 41, DCM

DiseaseAssertion:dilated cardiomyopathy

FamilyInfo:The proband reported that his mother died suddenly at approximately 35 years of age (specific cause unknown). Other family members were healthy with no history of cardiac disease. Written informed consent was obtained from all participants.

ParentalTesting:no parental testing reported. Sanger sequencing of available family members (daughter, half-brother, maternal uncle and maternal aunt) confirmed that none carried the variant, supporting its de novo origin

CasePresentingHPOs:HP:0002875, HP:0001644, HP:4000141, HP:6000313

CaseHPOFreeText: ECG showed sinus bradycardia, occasional atrial premature beats, delayed atrioventricular conduction, left atrial enlargement, left ventricular high voltage, incomplete right bundle branch block, and ST-T changes (Figure 1C). CMR revealed late gadolinium enhancement (LGE) in the basal to mid-septal and anterolateral segments of the left ventricle (Figure 1D).

CaseNotHPOs:HP:0000822, HP:0003077

CaseNotHPOFreeText:He denied a history of hyperlipidemia, hypertension, or substance abuse.

CasePreviousTesting:No reports of previous testing

Genotyping Method:whole-exome sequencing and Sanger sequencing

FunctionalAnalysis:not reported

Variant:c.547C>T p.Arg183Trp

ClinVar:43628

CAID:CA004294

gnomAD:Overall allele frequency: 0.000001239

AdditionalInfo:not reported

Case#: P16, 17 year old male

DiseaseAssertion: left ventricular noncompaction cardiomyopathy

FamilyInfo: His mother, sister, and grandfather on his mothers side also had LVNC

ParentalTesting: NR

CasePresentingHPOs: NR

CaseHPOFreeText: The patient had an abnormal structure in the left side of his heart. His heart ultrasound showed extra muscle ridges and deep spaces in the heart muscle.

CaseNotHPOs: NR

CaseNotHPOFreeText: The study did not report fainting, heart rhythm problems, blood clots, or heart failure for this patient.

CasePreviousTesting: Heart ultrasound, ECG, heart MRI, blood tests, and genetic testing.

Genotyping Method: Next generation sequencing followed by Sanger sequencing to confirm this gene change

FunctionalAnalysis: NR

Variant: NM_005159.5:c.329>T

Clinvar: 2137647

CAID: CA391631478

gnomAD: Exact frequency not provided

AdditionalInfo: The patient's heart pumping ability was 70 %on ultrasound. Researchers classified his ACTC1 variant as a variant of uncertain significance meaning they were not sure whether it causes diseases.

Case#: 33 year-old female; first cardiologic evaluation at age 24 (LV wall thickness 13 mm); re-evaluated at 33 after recurrent palpitations

DiseaseAssertion: Noonan syndrome (PTPN11) with sarcomeric hypertrophic cardiomyopathy (MYBPC3); non-obstructive HCM, mild phenotype

FamilyInfo: Father carries the MYBPC3 c.1790G>A variant and has HCM; the PTPN11 variant was absent in both parents, consistent with de novo. Both parents and the proband's brothers underwent full cardiologic evaluation, no cardiovascular disease in the other family members. Parents declined genetic testing of the underage siblings. Grandparents (I-1, I-2) and II-2, II-3 have unknown phenotypes (pedigree Fig. 2).

ParentalTesting: Both parents genotyped for the two proband variants (Table 1). Father heterozygous for MYBPC3 c.1790G>A; neither parent carries PTPN11 c.1510A>G, supporting de novo status. Phase between the two variants therefore established as in trans (different genes).

CasePresentingHPOs: HP:0001639; HP:0001962; HP:0004322; HP:0000271; HP:0001647; HP:0000508

CaseHPOFreeText: Regular psychophysical development. First echo at 24 showed mild increase in LV wall thickness (13 mm). At 33, presented with several episodes of palpitations; exam showed mild facial dysmorphisms (wide mouth, sloping forehead, prominent nasal bridge, prominent nose, low-set ears), short stature, and a systolic heart murmur. Echo: asymmetric LV hypertrophy, maximum wall thickness 16 mm at the anterior interventricular septum, mild mitral regurgitation, non-obstructive. No other cardiovascular signs.

CaseNotHPOs: HP:0001635; HP:0001650; HP:0001642; HP:0001250

CaseNotHPOFreeText: No heart failure, no LV outflow obstruction, no pulmonary stenosis, no other congenital heart defect. No intellectual disability; psychophysical development was regular. No other signs of cardiovascular disease on examination.

CasePreviousTesting: NGS panel of 325 cardiomyopathy-associated genes (Supplementary Table S1); MAF threshold 5%; variants validated by Sanger sequencing; cascade testing restricted to the two proband variants.

Genotyping Method: NGS targeted panel (Maxwell 16 DNA extraction, Agilent Alyssa analysis, Illumina Variant Interpreter, in-house pipeline) with Sanger validation; parental Sanger genotyping for the same two variants.

FunctionalAnalysis: None performed by the authors. They cite prior HeLa cell work showing the MYBPC3 c.1790G>A change causes exon 18 inclusion in the transcript and an almost undetectable 248 bp product.

Variant 1: PTPN11 NM_002834.3:c.1510A>G (p.Met504Val); heterozygous missense; de novo; classified pathogenic, explains Noonan syndrome

ClinVar: Not stated in the paper; verify the current record before submitting.

CAID: N/A

gnomAD: Not reported in the paper; I have not checked gnomAD for this variant.

Variant 2: MYBPC3 NM_000256.3:c.1790G>A (p.Arg597Gln); heterozygous missense; exon 18, last nucleotide of the exon, affecting a highly conserved residue and causing a splicing variation; inherited from the father

ClinVar: Not stated in the paper; authors note it is classified pathogenic/likely pathogenic for HCM in several genetic databases.

CAID: N/A

gnomAD: N/A

PMID: 32824488

Gene: MYBPC3

AdditionalInfo: Authors describe this as the first reported young adult with HCM and mild NS carrying variants in both PTPN11 and MYBPC3. Note the terminology problem: the abstract calls them "compound heterozygous," but the variants are in different genes on different chromosomes, so this is digenic (double heterozygosity), not compound heterozygosity. The authors argue the mild phenotype contrasts with the usual expectation that multiple sarcomeric hits worsen the disease, and that red flags justified the broad panel.

Case1: 40-year-old Chinese male

DiseaseAssertion: exertional dyspnea for one year and substernal chest pain for one week.

FamilyInfo: Father experienced sudden cardiac death (SCD) at the age of 41. Targeted region capture and second-generation high throughput sequencing were performed on the proband’s cousin, cousin sister, and sister. Results demonstrated that all family members carried the MYBPC3 c.1827dupC variant. Pedigree in Fig. 3

ParentalTesting: NR

CasePresentingHPOs: HP:0025169, HP:0025168, HP:0031675, HP:0001714,

CaseHPOFreeText: harsh systolic ejection murmur at the left sternal border (3rd–4th intercostal spaces), accentuated by Valsalva maneuver. Echocardiography revealed the following key findings: severe asymmetric septal hypertrophy, characterized by an interventricular septal thickness (IVsd) at end-diastole of 25–30 mm and a left ventricular posterior wall dimensions (LVPWd) of 21 mm, with a preserved left ventricular ejection fraction (LVEF) of 59%

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: target-region capture sequencing and second-generation high throughput sequencing were performed to analyze all exons and their Flanking regions. Rare and known variants were validated using Sanger sequencing and cascade screening was carried out for all available relatives

Genotyping Method: target-region capture sequencing and second-generation high throughput sequencing, Sanger sequencing and cascade screening.

FunctionalAnalysis:NR

Variant: NM_000256.3:c.1827dupC, NM_004415.4:c.1324T>C

ClinVar:NR

CAID:UnregisteredVariant

gnomAD:NR

Case#:a 40-year-old woman with a history of hypokinetic-dilative cardiomyopathy and heterozygous for TNNT2 gene mutation

DiseaseAssertion:hypokinetic-dilative cardiomyopathy

FamilyInfo: her family appreciated the clear communication, and as her condition improved without further complications, she expressed gratitude for the care provided.

ParentalTesting:n/r

CasePresentingHPOs:HP:0001644, HP:0002094, HP:0002094, HP:0001695,

CaseHPOFreeText:Progressive dyspnea and fatigue began in January 2017. In February 2018, the patient had cardiac arrest due to ventricular fibrillation at 26 weeks’ gestation, followed by emergency caesarean section. She carried a heterozygous TNNT2 variant (c.547C>T, p.Arg183Trp)

CaseNotHPOs: HP:0031972, HP:0031972

CaseNotHPOFreeText:Coronary angiography showed no significant stenosis.

CasePreviousTesting:Testing method and scope

GenotypingMethod:n/a

FunctionalAnalysis:not reported

Variant: c.547C>T p.Arg183Trp)

Clinvar:not known

CAID:CA391630526

gnomAD:n/r

AdditionalInfo:n/r

Case#: a 50‐year‐old male who was clinically diagnosed with isolated CS and prescribed with prednisolone without much effect, and subsequent genetic analysis revealed pathogenic variants in LMNA and TNNT2, representative genes for cardiomyopathy.

DiseaseAssertion:Dilated cardiomyopathy

FamilyInfo: not reported

ParentalTesting: He had no family history of heart disease or sudden death

CasePresentingHPOs:HP:0002094,HP:0005110,HP:0025169, HP:0005110

CaseHPOFreeText:Progressive cardiac conduction disease: first-degree AV block with left axis deviation on an earlier ECG progressed to high-grade and then complete AV block. At age 50, the patient also had mild dyspnoea on exertion (New York Class ll) and atrial fibrillation. The authors later stated that it was dilated cardiomyopathy.

CaseNotHPOs:HP:0033608,HP:0002716

CaseNotHPOFreeText:CT showed no enlarged lymph nodes, pulmonary nodules, or other organ abnormalities

CasePreviousTesting: whole‐exome sequencing analysis to evaluate the risk of inherited cardiomyopathies and identified two missense variants in TNNT2 (chr1:201364335(hg38), NM_001001430.3, c.422G>A, p.Arg141Gln) and LMNA (chr1:156136096(hg38), NM_170707.4, c.1132A>C, p.Lys378Gln) (Figure 3). Sanger sequencing analysis identified a heterozygous single‐base substitution (c.1132A>C) in the LMNA gene and c.422G>A in the TNNT2 gene (red arrows).

Genotyping Method:Whole-exome sequencing (WES) identified the variants; Sanger sequencing of the TNNT2 and LMNA variants is shown in Figure 3.

FunctionalAnalysis:Not reported

Variant:TNNT2: NM_001001430.3:c.422G>A (p.Arg141Gln),LMNA: NM_170707.4:c.1132A>C (p.Lys378Gln)

ClinVar:43637

CAID:CA004540

gnomAD:not reported

AdditionalInfo:not reported

Case#:A 65-year-old woman with severe hypertrophic cardiomyopathy

DiseaseAssertion:Severe hypertrophic cardiomyopathy

FamilyInfo:no information reported

ParentalTesting:no parental testing reported

CasePresentingHPOs:HP:0001639

CaseHPOFreeText: gene panel testing that identified a single variant

CaseNotHPOs: not found

CaseNotHPOFreeText: not found

CasePreviousTesting: gene panel testing that identified a single variant

Genotyping Method:clinical gene panel testing

FunctionalAnalysis: rapid insertion of TNNT2 gene variants into induced pluripotent stem cell-differentiated cardiomyocytes (iPSC-CMs) for functional annotation of the variants for (E251D)(Figure B)

Variant:c.753G>T (p.Glu251Asp)

ClinVar:not found

CAID:CA090003

gnomAD:not found

AdditionalInfo:not reported

Case#:A 70‐year‐old woman, previously healthy with a left ventricular ejection fraction presented with DCM

DiseaseAssertion:dilated cardiomyopathy and a 4-month history of progressive heart failure

FamilyInfo:"Family history was negative for IDC or heart failure (Figure 3), although an uncle (II‐3) reportedly had an enlarged heart, and three other relatives (II‐1, II‐2, and III‐4) had cardiac related deaths confirmed by death certificate. The proband’s father (II‐1) died of myocardial failure and pulmonary edema; her mother (II‐2) died of pulmonary embolism; and her sister (III‐4) died suddenly of coronary artery disease in her 60s. Her daughter, the proband’s niece (IV‐3), had a history of palpitations and lower extremity swelling, intermittent numbness, and blanching of the fingers at age 49. Her echocardiogram was normal. Her ECG showed nonspecific ST‐T wave changes and left anterior hemiblock."

ParentalTesting:no parental testing reported because both parents were deceased. The two offsprings that were reported were tested and carried both variants.

CasePresentingHPOs:HP:0001644, HP:0001635, HP:0002875, HP:0012378

CaseHPOFreeText:symptoms of progressive dyspnea on exertion and fatigue that began 2–3 months prior to her presentation. Also, she had an unrelenting progression of symptoms and was hospitalized with advanced NYHA Class IV heart failure 6 weeks later. Lastly, she received a heart transplant.

CaseNotHPOs:not reported

CaseNotHPOFreeText:no myocarditis or infiltrative process and no histological evidence of hemochromatosis,

CasePreviousTesting:Oligonucleotide hybridization‐based DNA sequencing was conducted in the proband for a panel of 19 DCM genes ( Table 1 )

Genotyping Method:Oligonucleotide hybridization‐based DNA sequencing and genomic DNA was extracted from whole blood and was sequenced in our laboratory in both directions to detect and/or confirm nucleotide variants in TNNT2 in the proband and the proband’s relatives using an Applied Biosystems 3130XL capillary sequencer

FunctionalAnalysis:R139H (Figure 4): Functional studies in porcine cardiac skinned fibers reconstituted with the mutant R139H troponin T protein showed decreased Ca2+ sensitivity at pH 7, characteristic of DCM.

Variant:416G>A (R139H) in exon 10 and 690–6G>A in intron 13.

ClinVar:not found

CAID:CA004513

gnomAD:not found

AdditionalInfo:not reported

Case#: 30 year old female athlete

DiseaseAssertion: Subclinical hypertrophic cardiomyopathy

FamilyInfo: Her mother has HCM and the same ACTC1 gene change. Her grandmother and uncle on her mothers side died suddenly.

ParentalTesting: Her mother tested positive for the ACTC1 gene change and there isn't any information about the father.

CasePresentingHPOs: NR

CaseHPOFreeText: The patient did not have dizziness, fainting, trouble breathing or chest pain. Her heart muscle was not thickened.

CaseNotHPOs: NR

CaseNotHPOFreeText: The patient sometimes felt her heart beating unusually during exercise. A heart MRI showed small changes in her heart muscle and heart valve.

CasePreviousTesting: The patient had an ECG, heart ultrasound, heart monitor and heart MRI

Genotyping Method:Sanger sequencing was used to test the ACTC1 gene.

FunctionalAnalysis: NR

Variant: ACTC1 p.Val11Leu

Clinvar: 2947021

CAID: CA391633409

gnomAD: NR

AdditionalInfo: The patient continued playing competitive sports and had regular heart checkups.

Case#: Family 3, III-4

DiseaseAssertion: Dilated cardiomyopathy

FamilyInfo: The family had multiple cases of DCM consistent with autosomal dominant inheritance.

ParentalTesting: NR

CasePresentingHPOs: Dilated cardiomyopathy (HP:0001644)

CaseHPOFreeText: Female age 41 with DCM. her left ventricular end diastolic diameter was 58 mm and her ejection fraction was 43%.

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: Echocardiogram and clinical cardiac evaluation

Genotyping Method: Sanger sequencing of KLF13

FunctionalAnalysis: The C199R mutation reduced KLF13 ability to activate ATC1 and MYH7 bind DNA and work together with GATA4.

Variant: KLF13 c.595T>C

Clinvar: NR

CAID: CA391512228

gnomAD: The variant was reported as absent from gnomAD at the time of the study.

AdditionalInfo: The variant was associated with familial aDCM and was not detected in the 418 healthy controls.

Case#: Female, Hispanic, 4

DiseaseAssertion:Dilated cardiomyopathy

FamilyInfo: Uncle who died at a young age of sudden cardiac death.

ParentalTesting:

CasePresentingHPOs: HP:0001638

"severe decompensated cardiomyopathy at age 4."

CaseHPOFreeText: NR

CaseNotHPOs: NR

CaseNotHPOFreeText:NR

CasePreviousTesting: NR

Genotyping Method: commercial genetic testing and Sanger sequencing

FunctionalAnalysis:

Variant: NM_001276345.2:c.*187C>T

ClinVar: NR

CAID:CA2649785730

gnomAD:NR

AdditionalInfo:

Case#: Family #6; 36-year-old male

DiseaseAssertion: Arrhythmogenic right ventricular cardiomyopathy (ARVC); diagnosed according to the 2010 revised Task Force Criteria

FamilyInfo: Family #6. No informative segregation evidence specifically linking the MYL3 variant to ARVC was reported. The authors noted that family screening was incomplete or normal in other families, but did not specify which circumstance applied to Family #6.

ParentalTesting: NR

CasePresentingHPOs: HP:0006682 (PVCs)

CaseHPOFreeText: Symptomatic presentation; major right ventricular structural abnormality; minor ECG repolarization criterion; 1,181 ventricular ectopic beats on Holter monitoring; sustained ventricular arrhythmia (specific rhythm not reported).

CaseNotHPOs: HP:0001279 (Syncope); HP:0005162 (Abnormal left ventricular function)

CaseNotHPOFreeText: No cardiac syncope or left ventricular dysfunction reported. Absence of cardiac syncope does not necessarily exclude every form of syncope.

CasePreviousTesting: No pathogenic or likely pathogenic variants identified in established ARVC-associated genes (PKP2, DSG2, DSP, DSC2, JUP, TMEM43, PLN, SCN5A). Subsequent screening included nine sarcomere genes: ACTC1, MYBPC3, MYH7, MYL2, MYL3, TNNC1, TNNI3, TNNT2, and TPM1. The study used broad genetic testing, including whole-exome sequencing in a subset of probands; whether Family #6 underwent whole-exome sequencing was not specified.

Genotyping Method: Sarcomere-gene sequencing and deletion/duplication analysis through clinical cardiomyopathy panels, research-based next-generation sequencing panels, or whole-exome sequencing. The exact initial platform for Family #6 was not specified. Identified variants were confirmed by PCR amplification and Sanger sequencing.

FunctionalAnalysis: NR

Variant: MYL3 NM_000258.2:c.461G>A (p.Arg154His); missense variant; exon 4

ClinVar: 14062

CAID: CA013861

gnomAD: MYL3 c.461G>A (p.Arg154His), GRCh38: 3-46859495-C-T. gnomAD v4: Exome AF = 0.00003557; Genome AF = 0.00001971; Total AF = 0.00003408. European (non-Finnish): AC = 52, AF = 0.00004407. https://gnomad.broadinstitute.org/variant/3-46859495-C-T?dataset=gnomad_r4

AdditionalInfo: Murray et al. (2018), Tables 1 and 2, Family #6. The MYL3 variant was classified as likely pathogenic (LP) according to ACMG criteria, with a PolyPhen-2 score of 0.861. The proband met criteria for definite ARVC, with no reported left ventricular dysfunction. Although the variant was rare and computationally predicted to be damaging, the authors emphasized that evidence demonstrating a causal relationship between sarcomere variants and ARVC remained insufficient. No direct functional analysis of this variant was performed in the study.

Case#: Female, 4 months, Swedish

DiseaseAssertion: dilated cardiomyopathy

FamilyInfo: Strong family history of DCM and faily history of SCD due to DCM. Maternal grandfather had enlarged left ventricle.

ParentalTesting:

CasePresentingHPOs: HP:0005162, HP:0031295, HP:0001653,

CaseHPOFreeText: enlarged left ventricle,

CaseNotHPOs:HP:0011947

CaseNotHPOFreeText: circulatory collapse

CasePreviousTesting: NR

Genotyping Method: Sanger sequencing

FunctionalAnalysis: NR

Variant: NM_001276345.2:c.548G>A

ClinVar:43649

CAID: CA004727

gnomAD:NR

AdditionalInfo: During cardiac catheterization, cardiac resuscitation due to circulatory collapse was needed.

Case1: Male, 37 years old, Colombian

DiseaseAssertion: asymmetric septal hypertrophic cardiomyopathy

FamilyInfo: During genetic assessment, a family history of hypertrophic cardiomyopathy (HCM) was detected. The patient’s mother had HCM and died at the age of 66; two living brothers have HCM (51 and 60 years of age). In addition, two of his brothers under the age of 35 died suddenly, two more brothers died from an unknown cause before the age of 5, and yet another brother is being examined for possible heart disease. Findings indicated a dominant inheritance pattern for HCM in this family. Pedigree shown in Figure 2.

ParentalTesting: NR

CasePresentingHPOs: HP:0001639, HP:0001663, HP:0001962, HP:000209, HP:0002315

CaseHPOFreeText: At the age of 25, his symptomatology started, including intense fatigue and mild thoracic pain due to physical activity. At the age of 32, an echocardiogram revealed asymmetric septal hypertrophic cardiomyopathy. The thickness of the interventricular septum was 19.5 mm in the basal third, 22 mm in the middle third, and 23 mm in the apical third, and ventricular tachycardia was also present. Alcohol septal ablation was performed. However, ventricular tachycardia and disabling symptoms persisted, so he required an implantable cardioverter-defibrillator at the age of 35. A routine echocardiogram at the age of 36 yielded the following findings: an LV of normal size, mild hypertrophy of the septum, normal systolic function, and diastolic dysfunction with slow LV relaxation. The patient still suffers dyspnea during physical effort and occasionally thoracic pain with palpitations

CaseNotHPOs: NR

CaseNotHPOFreeText: NR

CasePreviousTesting: NR

Genotyping Method: A molecular panel for HCM including 17 genes was performed using next-generation sequencing. Sanger sequencing chromatogram focusing on the targeted region including the variation

FunctionalAnalysis: NR

Variant: NM_000432.3:c.260G>C

ClinVar: 43461

CAID: CA009968

gnomAD: NR

AdditionalInfo: NR

Case#: V-1; male; age 28; Chinese family

DiseaseAssertion: Hypertrophic cardiomyopathy

FamilyInfo: V-1 is part of a large consanguineous HCM pedigree. Family segregation information was reported for the MYBPC3 variant. V-1 died suddenly at age 29

CasePresentingHPOs: HP:0001712 HP:0005144 HP:0032092

CaseHPOFreeText: Left ventricular hypertrophy; increased interventricular septal thickness; left ventricular outflow tract obstruction

Genotyping Method: Sanger sequencing and next-generation sequencing

Variant: c.3624delC, missense

ClinVar: 42727

CAID: CA014493

Case#: 2 year old, male, from Yunnan Province, China