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Table 1 MyHC-IIA variants by location and clinical features
figure a

From: Filamentous tangles with nemaline rods in MYH2 myopathy: a novel phenotype

Inheritance Pathogenic variant Subdomain Clinical features of pronounced ophthalmoparesis, with References
Motor head and neck
Autosomal Dominant (yellow bar) c.2166G>A, p.Glu706Lys SH1 helix Classical form: joint contractures in infancy (outgrown); progressive proximal limb muscle weakness; hand weakness and tremor; mild facial weakness; axial hyperlordosis and kyphoscoliosis [3, 14, 15, 29]
Autosomal recessive (green bar)
 Homozygous c.1009-1G>A, p.Ser337Leufs*11 Exon 10 skipping Dysphagia in infancy; ptosis; tall, thin, with scoliosis; mild truncal and proximal limb muscle weakness [36]
 Homozygous c.737 G>A p.Arg246His ATP-binding, Switch I Proximal and facial muscle weakness, ptosis, dysphagia, joint laxity [5]
 Homozygous c.2400delG, p.Phe801Serfs*28 IQ motif Facial, neck flexor, upper and proximal lower limb muscle weakness; scoliosis [12, 13]
 Homozygous c.2398delG, p.Gly800fs27* IQ motif Severe dysphagia in infancy, neck and proximal muscle weakness [31]
 Heterozygous c.904+1G>A, p.Tyr269-Glu302delfs*
c.2347C > T p. Arg783*
Exon 9
Actin binding—IQ motif
Facial, neck, elbow and ankle flexion; mild proximal muscle weakness; ptosis; joint hypermobility [25]
 Heterozygous c.1975-2A>G, p.Glu659-Gly687delfs*11
c.2405T>A p.Leu802*
Actin binding
IQ motif
Facial, upper and proximal lower limb, and abdominal muscle weakness; congenital pectus carinatum [27]
 Heterozygous c.1331C>T, p.Arg445Cys
c.2405T>A, p.Leu802*
Exon 12
IQ motif
Early childhood onset; facial, neck flexor, proximal arm, hand, hip flexor and abdominal muscle weakness [26]
 Homozygous c.533C>T, p.Thr178Ile ATP binding, P-loop Early childhood onset; facial, neck flexor, proximal limb and hand muscle weakness; lumbar lordosis [26]
 Homozygous c.706G>A, p.Ala236Thr ATP-binding, Switch I Early childhood onset; facial, neck flexor, proximal limb and hand muscle weakness [26]
 Homozygous c.1592T>C, p.Met531Thr Exon 14 Adolescent onset; facial, neck flexor, proximal limb and hand muscle weakness; finger contractures [26]
 Homozygous c.1498G>T, p.Glu500* Relay loop Neck flexor, proximal upper and lower limb muscle weakness; early cataracts [6]
Coiled-coil tail
Autosomal dominant (yellow bar) c.5609T>C, p.Leu1870Pro Helix heptad disruption, ‘d’ position Neonatal onset; severe dysphagia; facial muscle weakness and ptosis; scoliosis; waddling-steppage gait [2]
 Autosomal dominant (yellow bar) c.5630T>C p.Leu1877Pro Helix heptad disruption, ‘d’ position Dysphagia; prominent distal > proximal muscle weakness; ptosis; asymetrical scapular winging [1]
Autosomal recessive (green bar)     
 Homozygous c.4352delA, p.Lys1451Serfs*40 Exon 29, tail truncation Neonatal onset; facial, neck flexor, and proximal limb weakness; marked ptosis [26]
Motor head+coiled coil tail
Autosomal Recessive     
 Heterozygous (green bar) c.2377C>T, p.Arg793* IQ motif, truncation Proximal lower, then upper limb muscle weakness; scapular winging; ptosis and diplopia; waddling gait [30]
  c.4381G>T, p.Glu1461* Tail truncation   
 Heterozygous (black bar) c.1546T>G, p.Phe516Val Relay loop Upper limb and proximal lower limb muscle weakness; facial weakness and ptosis; joint laxity; waddling gait This report
  c.3331C>T, p.Gln1111* Tail truncation