Myology research highlights

Myotonic dystrophy type 1 (DM1) is an RNA-mediated disorder caused by a non-coding CTG repeat expansion that, in particular, provokes functional alteration of CUG-binding proteins. As a consequence, several genes with misregulated alternative splicing have been linked to clinical symptoms. In search for additional molecular mechanisms that would trigger functional defects in DM1, the authors … [Read more]

Congenital myopathies are heterogeneous inherited diseases of muscle characterized by a range of distinctive histologic abnormalities. Herein, the authors have studied a consanguineous family with congenital myopathy. Genome-wide linkage analysis and whole-exome sequencing identified a homozygous nonsense mutation in 3-hydroxyacyl-CoA dehydratase 1 (HACD1) in affected individuals. The mutation results in non-sense mediated decay of the … [Read more]

In prior open-label studies, eteplirsen, a phosphorodiamidate morpholino oligomer (PMO), enabled dystrophin production in Duchenne muscular dystrophy (DMD) with genetic mutations amenable to skipping exon 51. The present study used a double-blind placebo-controlled protocol to test eteplirsen’s ability to induce dystrophin production and improve distance walked on the 6-minute walk test (6MWT). DMD boys aged … [Read more]

An international Clinical Outcomes Group consisting of clinicians, scientists, patient advocacy groups, and industries identified a need for a scale to measure motor performance of the upper limb. This study reports the steps leading to the development of the Performance of the Upper Limb (PUL), a tool specifically designed for assessing upper limb function in … [Read more]

In this study, the authors aimed to develop RNA splicing biomarkers of disease severity and therapeutic response in myotonic dystrophy type 1 (DM1) and type 2 (DM2). In a discovery cohort, they used microarrays to perform global analysis of alternative splicing in DM1 and DM2. The newly identified splicing changes were combined with previous data … [Read more]

Myotonic dystrophy type 1 (DM1) is an inherited dominant muscular dystrophy caused by expanded CTG•CAG triplet repeats in the 3′ UTR of the DMPK1 gene, which produces a toxic gain-of-function CUG RNA. It has been shown that the severity of disease symptoms, age of onset and progression are related to the length of the triplet … [Read more]

Genetic defects in calpain3 (CAPN3) leads to Limb-Girdle Muscular Dystrophy type 2A (LGMD2A), a disease of the skeletal muscle that affects predominantly the proximal limb muscles. The authors of this study have previously demonstrated the potential of Adeno-Associated Virus (AAV)-mediated transfer of the CAPN3 gene to correct the pathological signs in a murine model for … [Read more]

In this retrospective study that took place over the last 30 years, the life expectancy in patients suffering from Duchenne muscular dystrophy (DMD) was investigated by analysing the role of ventilatory assistance and causes of death. One hundred and nineteen adult DMD patients were followed from 1981 to 2011 at the AFM Yolaine de Kepper … [Read more]

Phosphorodiamidate morpholino oligomer (PMO)-mediated exon skipping is among the more promising approaches to the treatment of several neuromuscular disorders including Duchenne muscular dystrophy. The main weakness of this approach arises from the low efficiency and sporadic nature of the delivery of charge-neutral PMO into muscle fibers, the mechanism of which is unknown. In this study, … [Read more]

Demyelinating Charcot-Marie-Tooth disease (CMT) and chronic inflammatory demyelinating polyneuropathy (CIDP) are both demyelinating polyneuropathies. The differences in nerve enlargement degree and pattern at multiple evaluation sites/levels are not well known. In this study, the authors investigated the differences in nerve enlargement degree and the distribution pattern of nerve enlargement in patients with demyelinating CMT and … [Read more]