Blog Archives

This natural history-controlled study evaluated the prognosis and progression of spinal and bulbar muscular atrophy (SBMA), a rare X-linked motor neuron disorder caused by trinucleotide repeat expansion in the AR (androgen receptor) gene, after long-term androgen suppression with leuprorelin acetate treatment. A total of 36 patients with SBMA were treated with leuprorelin acetate for up … [Read more]

GNE myopathy is a rare, autosomal recessive, inborn error of sialic acid metabolism, caused by mutations in GNE, the gene encoding UDP-N-acetyl-glucosamine-2-epimerase/N-acetylmannosamine kinase. The disease manifests as an adult-onset myopathy characterized by progressive skeletal muscle weakness and atrophy. There is no medical therapy available for this debilitating disease. Hyposialylation of muscle glycoproteins likely contributes to … [Read more]

  Nephropathic cystinosis is an autosomal recessive lysosomal disease in which cystine cannot exit the lysosome to complete its degradation in the cytoplasm, thus accumulating in tissues. Some patients develop a distal myopathy involving mainly hand muscles. Myopathology descriptions from only 5 patients are available in the literature. Here, the authors present a comprehensive clinical, … [Read more]

  Multinucleate cellular syncytial formation is a hallmark of skeletal muscle differentiation. Myomaker, encoded by Mymk (Tmem8c), is a well-conserved plasma membrane protein required for myoblast fusion to form multinucleated myotubes in mouse, chick, and zebrafish. This multinational study reports that autosomal recessive mutations in MYMK (OMIM 615345) cause Carey-Fineman-Ziter syndrome in humans (CFZS; OMIM … [Read more]

Spinal muscular atrophy (SMA) is a recessive disease caused by mutations in the SMN1 gene, which encodes the protein survival motor neuron (SMN), whose absence dramatically affects the survival of motor neurons. In humans, the severity of the disease is lessened by the presence of a gene copy, SMN2. SMN2 differs from SMN1 by a … [Read more]

Researchers from Genethon and the Institute of Myology, AFM-Téléthon laboratories, Inserm (UMR 1089, Nantes) and the University of London (Royal Holloway) demonstrated the efficacy of an innovative gene therapy in the treatment of Duchenne muscular dystrophy. Indeed, after injecting microdystrophin (a “shortened” version of the dystrophin gene) via a drug vector, the researchers managed to … [Read more]

X-linked myotubular myopathy (XLMTM), a severe congenital myopathy, is caused by mutations in the MTM1 gene located on the X chromosome. A majority of affected males die in the early postnatal period, whereas female carriers are believed to be usually asymptomatic. Nevertheless, several affected females have been reported. To assess the phenotypic and pathological spectra … [Read more]

  This study describes two cases of myasthenia gravis (MG) with double seropositivity for acetylcholine receptor (AChR) and low-density lipoprotein receptor-related protein 4 (LRP4) antibodies (AChR/LRP4-MG) with invasive thymoma. Both cases showed myasthenic weakness, which was restricted to the ocular muscles for >5 months from onset, and then unprovoked severe clinical deterioration supervened with predominant … [Read more]

In spinal muscular atrophy (SMA), degeneration of motor neurons causes progressive muscular weakness, which is caused by homozygous deletion of the SMN1 gene. Available epidemiological data on SMA are scarce, often outdated, and limited to relatively small regions or populations. Combining data from different sources including genetic laboratories and patient registries may provide better insight … [Read more]