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

ABSTRACT: The MYH2 gene encodes the skeletal muscle myosin heavy chain IIA (MyHC-IIA) isoform, which is expressed in the fast twitch type 2A fibers. Autosomal dominant or recessive pathogenic variants in MYH2 lead to congenital myopathy clinically featured by ophthalmoparesis and predominantly proximal weakness. MYH2-myopathy is pathologically characterized by loss and atrophy of type 2A fibers. Additional myopathological abnormalities have included rimmed vacuoles containing small p62 positive inclusions, 15-20 nm tubulofilaments, minicores and dystrophic changes. We report an adult patient with late-pediatric onset MYH2-myopathy caused by two heterozygous pathogenic variants: c.3331C>T, p.Gln1111* predicted to result in truncation of the proximal tail region of MyHC-IIA, and c.1546T>G, p.Phe516Val

SUBMITTER: Madigan NN 

PROVIDER: S-EPMC8082902 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature