Myopathy Can Be A Key Phenotype Of Membrin (Gosr2) Deficiency

Pathogenic variants in Golgi snap receptor complex member 2 (GOSR2) cause progressive myoclonus epilepsy with ataxia, areflexia, elevated serum creatine kinase and loss of ambulation. Most reported patients are homozygous for the same pathogenic variant and follow the same disease course. A few severe exceptions with different pathogenic variants suffer from early onset and rapid progression of the disease with a congenital muscular dystrophy phenotype. Although most patients are reported to have elevated creatine kinase levels, neuromuscular involvement has only been described in the severe congenital cases. Here, we present a patient with two novel pathogenic variants in GOSR2, who despite a milder disease presentation shows profound neuromuscular involvement. This is the first case showing muscular dystrophy in a patient with late onset of the disease, thus expanding the phenotype of the disease caused by pathogenic variants in GOSR2. This article is protected by copyright. All rights reserved.