Congenital myopathies
RSS feedThe evolution of the new Morimoto-Ruy-Malicdan syndrome described in two brothers
In a previous study published in 2024, Marie Morimoto et al. described nine cases of a new congenital myopathy linked to biallelic variants of the RFC4 gene, the Morimoto-Ruy-Malicdan syndrome. This syndrome is characterised by coordination problems, muscular and respiratory weakness, hearing impairment, weight loss and cerebellar atrophy. A new study of two brothers of … [Read more]
A revision of the classification of congenital myopathies in the light of recent discoveries
The team at the Créteil Neuromuscular Disease Reference Centre takes stock of congenital myopathies in the light of the recent exponential increase in knowledge in this field: in addition to the histological criteria which largely contributed to their original descriptions, genetics has enabled new entities to be discovered and their contours to be better defined, … [Read more]
Long-term data on the evolution of patients with congenital myopathy
The Centre de référence des maladies neuromusculaires of the Institute of Myology conducted a single-centre observational study of 142 adult patients with congenital myopathy followed up between 1996 and 2019, for a median duration of 8 years. Congenital myopathies with cores linked to the RYR1 gene and centronuclear myopathies linked to the DNM2 gene were … [Read more]
A therapeutic advance in myopathies related to the RYR1 gene
Swiss researchers have undertaken preclinical work to pharmacologically treat one of the forms of myopathy linked to the ryanodine receptor type 1 (RYR1) : the model used for this research was a composite heterozygous mouse for two pathogenic variants of the RYR1 gene (p.Q1970fsX16 and p.A4329D) these mice were treated for 15 weeks with 0.05 … [Read more]
The manifestations of type 6 nemalin myopathy are modest but have a major impact on patients
A Dutch team has studied 24 patients with nemalin myopathy type 6, linked to mutations in KBTBD13 and the most prevalent in the Netherlands. Since childhood, patients have mainly suffered from muscle weakness, slowness of movement, muscle stiffness, difficulty running, fatigue and myalgia. Falls were reported by 71% of patients; over a prospective three-month period, … [Read more]
Cochrane meta-analysis in preparation on therapies for RYR1-related myopathies
An international consortium of clinicians led by a South African neuropaediatrician has presented a protocol designed to analyse the impact of different therapeutic interventions in muscle-expressing diseases associated with abnormalities of the RYR1 gene: the study will be based on the Cochrane methodology for meta-analysis of the literature on the subject, 7 experts have been … [Read more]
Targeted inhibition of ORAI1 reduces tubular aggregates in mice
Tubular aggregate myopathy may be due to overactivation of Store Operated Ca2+ Entry (SOCE) as a result of a gain-of-function variant in the STIM1 or ORAI1 genes. ORAI1 is a T-tubule membrane calcium channel that is activated by STIM1, a sarcoplasmic reticulum membrane protein that senses depletion of intracellular calcium stores. KO mice for ORAI1 … [Read more]
Mavacamten for 4 weeks does not improve the condition of mice models of nebulin-related nemalin myopathy
In muscle fibers from individuals with nebulin-related nemaline myopathy (NEB-NM) and in NEB-NM mouse models, the proportion of myosin in the disordered relaxed state and ATP consumption are abnormally increased, accompanied by a reshuffling of the energy proteome of these cells. Mavacamten, which reduces the amount of myosin in the disordered relaxed state in hypertrophic … [Read more]
Loss of function of JPH1, which encodes junctophilin, causes congenital myopathy
Four individuals from unrelated consanguineous families, two of European origin, one of Khmer origin and one of Middle Eastern origin all presented with congenital myopathy with: neonatal hypotonia, difficulty sucking, cleft palate, club feet ; generalized weakness predominantly in the lower limbs; myopathic facies, bilateral ptosis, ophthalmoplegia and fatigability; muscle biopsy revealed a predominance of … [Read more]
Overview of the main myopathies that can begin in the over-50s
A French review has set out to provide an overview of the most emblematic late-onset myopathies (LOMs), those which may appear after the age of 50, and to identify the pitfalls to be avoided and the important steps in the diagnostic approach to these pathologies. Based on an assessment of the literature and medical data … [Read more]
