Case: Bolino Proband 1 (proband 1945), male, reported at 4yo, symptom onset at 42mo
CasePresentingHPOs: HP:0001349, HP:0003701, HP:0001284, HP:0001288, HP:0003474, HP:0003693, HP:0003722, HP:0003391, HP:0001761, HP:0003383, HP:0012447 (bilateral facial weakness, proximal muscle weakness, areflexia, abnormal gait, sensory impairment, distal limb muscle atrophy, neck flexor weakness, Gower's sign, pes cavus, onion bulb formation, abnormal myelination)
HPOsFreeText: walked at 14mo, eyes reported to be normal, gait - bilateral steppage, pes equinovarus deformity of both feet, frequent falling, had normal early motor milestones, bilateral pes cavus with retraction of Achille's tendon, intellectually normal. Laboratory testing normal: full blood count, fasting blood glucose, serum electrolytes, creatine kinase, lactic acid, urinary organic acids, serum and urine carnitine, EEG, ECG, and liver echography, segmental demyelination in 92% of fibers, redundant loops of myelin sheath irregularly arrayed near axon, muscle biopsy of rectus femoris showed atrophic and angulated fibers in clusters and large type grouping, lipid accumulation
Median nerve conduction studies: compound motor action potential = 4.6uV, distal motor latency = 7.8msec, sensory action potential = 3.3uV, motor nerve conduction velocity = 17msec, sensory nerve conduction velocity = 18msec
Peroneal nerve conduction studies: compound motor action potential = 0.21uV, distal motor latency = 7.8msec, motor nerve conduction velocity = 14
Sural nerve conduction studies: sensory action potential = no response, sensory nerve conduction velocity = no response
CountryOrigin: Italy
FamilyInfo: consanguineous family, parents reported to be normal at clinical and electrophysiological exams
PreviouslyPublished: PMID:10673338, PMID:8817346, PMID: 8628474, PMID: 8017168
GenotypingMethod: RT-PCR of RNA from patient lymphoblastoid cell line, available family members analyzed and segregation of variant with disease confirmed in pedigree - PMID:8817346 - homozygosity mapping and haplotype sharing through microsatellite and linkage analysis
Variant: NM_016156.5(MTMR2):c.1276C>T (p.Gln426Ter) homozygous
ClinVar: 6231, https://www.ncbi.nlm.nih.gov/clinvar/variation/6231/
gnomAD: 0.000007085, https://gnomad.broadinstitute.org/variant/11-95578227-G-A