Myology research highlights

Isis Pharmaceuticals has initiated a pivotal Phase III study evaluating ISIS-SMNRx in infants with spinal muscular atrophy (SMA), the most common genetic cause of infant mortality. The Phase III study entitled ENDEAR, is the first of several planned studies in a broad and comprehensive late-stage clinical development program for ISIS-SMNRx.  ENDEAR is a randomized, double-blind, … [Read more]

Mutations in fukutin-related protein (FKRP) gene cause a wide spectrum of disease phenotypes including the common limb-girdle muscular dystrophy 2I (LGMD2I), the severe Walker-Warburg syndrome, and muscle-eye-brain disease. FKRP deficiency results in α-dystroglycan (α-DG) hypoglycosylation in the muscle and heart, which is a biochemical hallmark of dystroglycanopathies. To study gene replacement therapy, the authors generated … [Read more]

There are no validated criteria for the diagnosis of sensory neuronopathy (SNN) yet. In a preliminary monocenter study, a set of criteria relying on clinical and electrophysiological data showed good sensitivity and specificity for a diagnosis of probable SNN. The aim of this study was to test these criteria in a French multicenter study. A … [Read more]

This study reports on a 5-year-old girl who presented with an association of symptoms reminiscent of an Ullrich-like congenital muscular dystrophy including congenital hypotonia, proximal joint contractures, hyperlaxity of distal joints, normal cognitive development, and kyphoscoliosis. There was an excess of neuromuscular spindles on the skeletal muscle biopsy. This very peculiar feature on muscle biopsy … [Read more]

Centronuclear myopathies (CNMs) are characterized by muscle weakness and increased numbers of central nuclei within myofibers. X-linked myotubular myopathy, the most common severe form of CNM, is caused by mutations in MTM1, encoding myotubularin (MTM1), a lipid phosphatase. To increase understanding of MTM1 function, the authors of this study conducted a yeast two-hybrid screen to … [Read more]

Autosomal recessive muscular dystrophies are heterogeneous genetic disorders. To date, 39 genes are implicated. Genetic diagnosis using targeted single-gene analysis by Sanger sequencing yields negative results in 10-20% of samples, warranting clinical re-evaluation and time-consuming testing of additional genes. This applies to dysferlinopathies caused by mutations in the gene encoding dysferlin (DYSF), which presents mainly … [Read more]

Pompe disease is a rare, autosomal recessive disorder characterized by deficiency of lysosomal acid alpha-glucosidase and accumulation of lysosomal glycogen in many tissues. The variable clinical manifestations, broad phenotypic spectrum, and overlap of signs and symptoms with other neuromuscular diseases make diagnosis challenging. In the past, the diagnosis of Pompe disease was based on enzyme … [Read more]

Spinal and bulbar muscular atrophy (SBMA) is an X-linked neuromuscular disease caused by a trinucleotide (CAG) repeat expansion in the androgen receptor gene. Patients with SBMA have weakness, atrophy, and fasciculations in the bulbar and extremity muscles. Individuals with CAG repeat lengths greater than 62 have not previously been reported. Here, the authors evaluated a … [Read more]

The decrease in muscle strength in patients with Duchenne muscular dystrophy (DMD) is mainly explained by a decrease in the number of active contractile elements. Nevertheless, it is possible that other electro-chemical and force transmission processes may contribute. The present study aimed to quantify the effect of DMD on the relative contribution of electro-chemical and … [Read more]

In this study, the authors aimed to assess the frequency, location, severity, duration, and fluctuation over time of muscle cramps in Charcot-Marie-Tooth Disease (CMT). Inherited Neuropathies Consortium Contact Registry participants recorded the occurrence and characteristics of muscle cramps using an 11-question survey administered 3 times over 8 weeks. A  total of 110 adult patients with … [Read more]