Myology research highlights

Congenital myasthenic syndromes (CMS) are a group of inherited disorders that arise from impaired signal transmission at the neuromuscular synapse. They are characterized by fatigable muscle weakness. This is a heterogeneous group of disorders with 15 different genes implicated in the development of the disease. Using whole-exome sequencing the authors of the present study identified … [Read more]

The molecular basis underlying the clinical variability in symptomatic Duchenne muscular dystrophy (DMD) carriers are still to be precised. This article describes 26 cases of early symptomatic DMD carriers followed in the French neuromuscular network. Clinical presentation, muscular histological analysis and type of gene mutation, as well as X-chromosome inactivation (XCI) patterns using DNA extracted … [Read more]

Dystroglycanopathies are a clinically and genetically diverse group of recessively inherited conditions ranging from the most severe of the congenital muscular dystrophies, Walker-Warburg syndrome, to mild forms of adult-onset limb-girdle muscular dystrophy. Their hallmark is a reduction in the functional glycosylation of α-dystroglycan, which can be detected in muscle biopsies. An important part of this … [Read more]

Hereditary motor and sensory disorders of the peripheral nerve form one of the most common groups of human genetic diseases collectively called Charcot-Marie-Tooth (CMT) neuropathy. Using linkage analysis in a three-generation kindred, the authors of this study mapped a new locus for X-linked dominant CMT to chromosome Xp22.11. A microsatellite scan of the X chromosome … [Read more]

Researchers from the Institute of Myology recently demonstrated the remarkable efficiency of self-complementary (sc) AAV9 vectors for central nervous system (CNS) gene transfer following intravenous delivery in mice and larger animals. In this article, the same researchers investigated whether gene delivery to motor neurons (MNs) could also be achieved via intramuscular (i.m.) scAAV9 injection and … [Read more]

Pontocerebellar hypoplasia with spinal muscular atrophy, also known as PCH1, is a group of autosomal recessive disorders characterized by generalized muscle weakness and global developmental delay commonly resulting in early death. Gene defects had been discovered only in single patients until the recent identification of EXOSC3 mutations in several families with relatively mild course of … [Read more]

Approximately 50% of people with myasthenia gravis present with purely ocular symptoms so called ocular myasthenia. Of these, 50% to 60% develop generalized disease, most within two years. Their management is controversial. This is an update of a review first published in 2006 and previously updated in 2008 and 2010. This update aimed to assess … [Read more]

No effective treatment exists for patients with X-linked myotubular myopathy (XLMTM), a fatal congenital muscle disease caused by deficiency of the lipid phosphatase, myotubularin. Mtm1δ4 and Mtm1 p.R69C mice model severely- and moderately-symptomatic XLMTM, respectively, due to differences in the degree of myotubularin deficiency. Contractile function of intact EDL and soleus muscles from Mtm1δ4 mice, … [Read more]

Frequency and severity of cardiac involvement in DM2 are still controversial. The aims of this study were to determine the frequency and progression of cardiac and muscle involvement in a relatively large cohort of patients with DM2 throughout Italy and Germany and to provide long-term outcomes in this disorder. One hundred and four DM2 and … [Read more]

Upper limb assessment in non-ambulant patients remains a challenge. Jean-Yves Hogrel and his colleagues from the Institute of Myology have designed new tools to precisely assess pinch (MyoPinch), grip (MyoGrip), wrist flexion and extension (MyoWrist) strength. They have also designed a new tool to assess the ability of patients to produce repetitive flexion/extension movements of … [Read more]