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ACTA1-myopathy with prominent finger flexor weakness and rimmed vacuoles.

ABSTRACT: Actinopathy is a group of clinically and pathologically heterogeneous myopathies due to mutations in the skeletal muscle sarcomeric ?-actin 1-encoding gene (ACTA1). Disease-onset spans from prenatal life to adulthood and weakness can preferentially affect proximal or distal muscles. Myopathological findings include a spectrum of structural abnormalities with nemaline rods being the most common. We report a daughter and father with prominent finger flexors and/or quadriceps involvement. Muscle biopsies revealed rimmed vacuoles in both patients, associated with type 1 fiber atrophy in the daughter, and nemaline rods in the father. Next generation sequencing identified a novel dominant ACTA1 variant, c.149G>A (p.Gly50Asp) in both individuals and no abnormal variants in vacuolar myopathy-associated genes. Our findings expand the clinico-pathological spectrum of actinopathy.

SUBMITTER: Liewluck T

PROVIDER: S-EPMC6812538 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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ACTA1-myopathy with prominent finger flexor weakness and rimmed vacuoles.

Liewluck Teerin T Niu Zhiyv Z Moore Steven A SA Alsharabati Mohammad M Milone Margherita M

Neuromuscular disorders : NMD 20190302 5

Actinopathy is a group of clinically and pathologically heterogeneous myopathies due to mutations in the skeletal muscle sarcomeric α-actin 1-encoding gene (ACTA1). Disease-onset spans from prenatal life to adulthood and weakness can preferentially affect proximal or distal muscles. Myopathological findings include a spectrum of structural abnormalities with nemaline rods being the most common. We report a daughter and father with prominent finger flexors and/or quadriceps involvement. Muscle bi ...[more]

PMID: 30987788

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Atypical presentation of GNE myopathy with asymmetric hand weakness.

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