Myology research highlights

Myosin myopathies comprise a group of inherited diseases caused by mutations in myosin heavy chain (MyHC) genes. Homozygous or compound heterozygous truncating MYH2 mutations have been demonstrated to cause recessive myopathy with ophthalmoplegia, mild-to-moderate muscle weakness and complete lack of type 2A muscle fibers. In this study, the authors describe for the first time the … [Read more]

McArdle disease is a nonlysosomal glycogenosis that classically manifests with exercise-induced pain from childhood. Fixed weakness may occur from the fifth decade and is typically mild and located around the shoulder girdle. Here, the authors describe a 61-year-old man with exercise-induced pain from a young age and a 3-year history of weight loss and an … [Read more]

Most evidence supporting the benefit of thymectomy in juvenile myasthenia gravis (JMG) is extrapolated from adult studies, with only little data concerning paediatric populations. Here, the authors evaluate the outcome of children with generalized JMG who underwent thymectomy between 1996 and 2010 at 2 tertiary paediatric neurology referral centres in the United Kingdom. Twenty patients … [Read more]

A variable proportion of patients with generalized myasthenia gravis (MG) have autoantibodies to muscle specific tyrosine kinase (MuSK). During development, agrin, released from the motor nerve, interacts with low density lipoprotein receptor-related protein-4 (LRP4), which then binds to MuSK; MuSK interaction with the intracellular protein Dok7 results in clustering of the acetylcholine receptors (AChRs) on … [Read more]

 Recent studies show that patients with myotonic dystrophy (DM) have an increased risk of specific malignancies, but estimates of absolute cancer risk accounting for competing events are lacking. Using the Swedish Patient Registry, the authors identified 1,081 patients with an inpatient and/or outpatient diagnosis of DM between 1987 and 2007. Date and cause of death … [Read more]

Duchenne and Becker muscular dystrophies (DMD/BMD) are X-linked inherited muscular disorders caused by mutations in the dystrophin gene. Two-thirds of DMD cases are thought to be caused by inheritance from carrier mothers and this study aimed to clarify and compare the carrier frequency of mothers of DMD and BMD patients according to the mutation type. … [Read more]

This report examined demographic and clinical data collected during a randomised controlled trial, to describe the clinical spectrum of a large and well-defined cohort of Charcot–Marie–Tooth disease type 1A (CMT1A) patients. Among the 189 symptomatic patients screened, three patients (1.6%) reported first symptoms in the upper limbs, which may be misleading when establishing the clinical … [Read more]

In this article, the authors studied a two-generation family presenting with conditions that included progressive permanent weakness, myopathic myopathy, exercise-induced contracture before normokalaemic periodic paralysis or, if localized to the tibial anterior muscle group, transient compartment-like syndrome (painful acute oedema with neuronal compression and drop foot). 23Na and 1H magnetic resonance imaging displayed myoplasmic sodium … [Read more]

This study aimed to identify mutations in the inverted formin-2 (INF2) gene in patients with Charcot-Marie-Tooth (CMT) disease combined with focal segmental glomerulosclerosis (FSGS) in order to expand the genetic and phenotypic spectrum. INF2 was sequenced in 5 patients with CMT disease and FSGS. Mutations were subsequently screened in family members of the index patient … [Read more]

Charcot-Marie-Tooth (CMT) neuropathies represent a heterogeneous group of peripheral nerve disorders affecting 1 in 2500 persons. One variant, CMT1A, is a primary Schwann cell disorder, and represents the single most common variant. In previous studies the authors showed that neurotrophin-3 (NT-3) improved the tremblerJ (TrJ) mouse and also showed efficacy in CMT1A patients. Long-term treatment … [Read more]