Supplementary Table S1 & S2 Proband and Variant Information:

Case11: GT12, Female, 61, French

DiseaseAssertion: Glanzmann thrombasthenia

FamilyInfo: Brother (died at birth) this is all the information Supp table S1 gives

ParentalGenotype: N/A

CasePresentingHPOs: HP:0000421, HP:0000978, HP:0000790

(Epistaxis, easy bruising, hematuria)

CaseHPOFreeText: Heavy bleeding and menarche

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: Flow cytometry showed <5% variant expression of αIIbβ3 (See Supplementary Table 1)

PlateletAggregation: Absent platelet aggregation (See Supplementary Table 1)

CasePreviousTesting: Sanger sequencing of ITGA2B and ITGB3

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669

gnomAD: MAF in the European (non-Finnish) population 0.00002638 http://gnomad.broadinstitute.org/variant/17-45362012-C-T

Supplementary Table S1 & S2 Proband and Variant Information:

Case4: GT5, Male, 7, French

DiseaseAssertion: Glanzmann thrombasthenia

FamilyInfo: 1 brother, that is all Supp table S1 states

ParentalGenotype: N/A

CasePresentingHPOs: HP:0000421, HP:0000978, HP:0002138

(Epistaxis, easy bruising, subararachnoid hemorrhoid)

CaseHPOFreeText: Post-traumatic bleeding

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: N/A

PlateletAggregation: Absent platelet aggregation (See Supplementary Table 1)

CasePreviousTesting: Sanger sequencing of ITGA2B and ITGB3

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser) and NM_000212.2:c.2113del (p.Leu705Cysfs*4)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669 and CA8623443

gnomAD: MAF in the European (non-Finnish) population is 0.00002638 http://gnomad.broadinstitute.org/variant/17-45362012-C-T and MAF in the East Asian population is 0.0001087 http://gnomad.broadinstitute.org/variant/17-45380183-TC-T

Case7: Female, elderly (age not specified)

DiseaseAssertion: Glanzmann thrombasthenia type 1

FamilyInfo: N/A

ParentalGenotype: N/A

CasePresentingHPOs: N/A

CaseHPOFreeText: Severe bleeding when younger

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: N/A

PlateletAggregation: Minimal information, not specific enough

CasePreviousTesting: Sanger sequencing identified disease-causing variants in 18 out of 20 patients (Probands 6 and 14 excluded) with istoantibodies to αIIbβ3. The mutations were evenly distributed between ITGB3 and ITGA2B.

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669

gnomAD: MAF in the European (non-Finnish) population is 0.00002638 https://gnomad.broadinstitute.org/variant/17-45362012-C-T

Supplementary Table S1:

Case4: GT5, French, age and ethnicity not specified

DiseaseAssertion: Glanzmann thrombasthenia type I

FamilyInfo: N/A

ParentalGenotype: N/A

CasePresentingHPOs: N/A

CaseHPOFreeText: All patients had a life-long history of mucocutaneous bleeding

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: All patients in this study met the clinical and platelet function requirements for GT-- this includes an absent or strongly reduced expression of alphaIIbBeta3 in platelets

PlateletAggregation: All patients in this study met the clinical and platelet function requirements for GT-- this includes absent or severely reduced platelet aggregation with at least three physiological agonists

CasePreviousTesting: Sanger sequencing was performed. Sanger sequencing ensured coverage of all exons and splice sties of the ITGA2B and ITGB3 genes and extended 300-500 bp into the introns as well as including the UTR. They sequenced 416 bp upstream of the ITGA2B promoter and 463 bp upstream of the ITGB3 promoter. In total they sequenced 51.2% of the ITGA2B gene and 19.4% of the larger ITGB3 gene

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser) and NM_000212.2:c.2113del (p.Leu705Cysfs*4)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669 and CA8623443

gnomAD: MAF in the European (non-Finnish) population is 0.00002638 https://gnomad.broadinstitute.org/variant/17-45362012-C-T and MAF in the East Asian population is 0.0001087 https://gnomad.broadinstitute.org/variant/17-45380183-TC-T

Supplementary Table S1:

Case11: GT12, French, age and gender not specified

DiseaseAssertion: Glanzmann thrombasthenia type I

FamilyInfo: N/A

ParentalGenotype: N/A

CasePresentingHPOs: N/A

CaseHPOFreeText: All patients had a life-long history of mucocutaneous bleeding

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: All patients in this study met the clinical and platelet function requirements for GT-- this includes an absent or strongly reduced expression of alphaIIbBeta3 in platelets

PlateletAggregation: All patients in this study met the clinical and platelet function requirements for GT-- this includes absent or severely reduced platelet aggregation with at least three physiological agonists

CasePreviousTesting: Sanger sequencing was performed. Sanger sequencing ensured coverage of all exons and splice sties of the ITGA2B and ITGB3 genes and extended 300-500 bp into the introns as well as including the UTR. They sequenced 416 bp upstream of the ITGA2B promoter and 463 bp upstream of the ITGB3 promoter. In total they sequenced 51.2% of the ITGA2B gene and 19.4% of the larger ITGB3 gene

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669

gnomAD: MAF in the European (non-Finnish) population is 0.00002638 https://gnomad.broadinstitute.org/variant/17-45362012-C-T

Case7: (GT-7) Female, 57 years old, French

DiseaseAssertion: Glanzmann thrombasthenia

FamilyInfo: N/A

ParentalGenotype: N/A

CasePresentingHPOs: N/A

CaseHPOFreeText: Mucocutaneous bleeding

CaseNotHPOs: N/A

ProteinExpression: <5% surface expression levels of αIIbβ3

Platelet Aggregation: Absent platelet aggregation to all agonists (no mention for which agonists or response to ristocetin)

CasePreviousTesting: All the information we are given is "mutation screening of the ITGA2B and ITGB3 genes" the method for sequencing etc. was not stated

Gene: ITGB3

Variant: NM_000212.2:c.565C>T (p.Pro189Ser)

LegacyVariant: (p.Pro163Ser) (The paper gives legacy and current nomenclature)

ClinVar: N/A

CAiD: CA291224669

gnomAD MAF in the European (non-Finnish) population is 0.00002638 https://gnomad.broadinstitute.org/variant/17-45362012-C-T

Case1: Female, 49 years old, French

DiseaseAssertion: Glanzmann thrombasthenia (diagnosed when 5 years old)

FamilyInfo: A brother died from hemorrhage when he was 4 years old, but an adult sister has never experienced untoward bleeding. (Case History Supp Table 1)

ParentalGenotype: N/A

CasePresentingHPOs: HP:0000978, HP:0004406, HP:0000132, HP:0000225, HP:0000790

(Easy bruising, recurrent epistaxis, menorrhagia, gingival bleeding, hematuria

CaseHPOFreeText: Mucocutaneous bleeding

CaseNotHPOs: N/A

CaseNotHPOsFreeText: N/A

ProteinExpression: Flow cytometry analysis showed no biding of P2 and AP-2, two MoAbs recognizing alphaIIbBeta3 and a very weak binding of MoAbs to Beta3 to platelets of the proband

PlateletAggregation: Platelet function testing confirmed an absence of aggregation to ADP, collagen, arachidonic acid and thrombin but the response to ristocetin was normal (Case History Supp Table 1)

CasePreviousTesting: Direct sequencing of all exons and splice sites of ITGA2B (30 exons) and ITGB3 (15 exons) was performed by the French National Sequencing Center. Briefly, exons and flanking regions of ITGA2B and ITGB3 were amplified by PCR with a high fidelity Taq polymerase permitting large fragment amplification. PCR fragments were sequenced.

Gene: ITGB3

Variant: (p.Pro189Ser)

LegacyVariant: N/A

ClinVar: N/A

CAiD: CA291224669

gnomAD: MAF in European (non-Finnish) population is 0.00002638 http://gnomad.broadinstitute.org/variant/17-45362012-C-T