Myofibrillar myopathies
RSS feedA new case of myopathy secondary to digenismus
Russian researchers have published a study of a sibling with a diagnosis of myopathy linked jointly to the SPRK3 and TTN genes: two brothers aged 6 and 10 presented with a congenital myopathy that was very early onset but not very progressive. Their whole exome genotyping revealed a pathogenic variant in the gene encoding titin … [Read more]
A mutation in HSPB8 leads to axial and proximal myofibrillar myopathy beginning in childhood
While mutations in HSPB8 have been associated with distal hereditary motor neuropathy (dHMN2A) or Charcot-Marie-Tooth disease type 2L, five variants (including four affecting the last exon) of this gene have been linked to a distal form of myopathy beginning in adulthood. A Chinese team reports a first case of an 18-year-old girl with : a … [Read more]
Towards a better assessment of complex cases of titinopathy
The large size of the TTN gene encoding titin and the existence of numerous isoforms make it difficult to interpret genomic variants. An international consortium provides an update on this issue: 12 cases of suspected titinopathy, one of which had already been published, have been the subject of further studies with the aim of determining … [Read more]
Heart transplants and muscular dystrophies: reticence shattered
A review of the literature on the 275 heart transplants performed for muscular dystrophies up to July 2023 shows that : these operations involved 116 patients with Becker’s myopathy (BMD) and 102 with laminopathy, but also 17 patients with limb-girdle muscular dystrophy (LGMD), 12 with Steinert’s myotonic dystrophy (DM1), 11 with Duchenne muscular dystrophy (DMD), … [Read more]
Mutations in the SRPK3 gene only lead to skeletal muscle myopathy in combination with a mutation in the TTN gene
An international collaboration describes a cohort of 33 patients with slowly progressive myopathy, beginning in childhood and associated with co-segregation of SRPK3 and TTN variants. Axial and proximal muscle involvement affected the lower limbs more than the upper limbs. Respiratory muscle involvement was present in 14 of the patients; three had dilated cardiomyopathy probably due … [Read more]
Overview of neuromuscular diseases
After a brief reminder of the structure of the motor unit and the various modes of inheritance, this document provides short descriptions of the neuromuscular diseases that are part of our scope at AFM-Téléthon, as well as how to manage and treat them. For each group of diseases, as well as in the motor unit … [Read more]
Mitochondrial abnormalities are at the core of the cardiac damage observed in desminopathies
French researchers, supported by AFM-Téléthon, have been investigating the pathophysiological mechanisms behind the cardiopathies frequently observed in primary desminopathies, the most common form of myofibrillar myopathy: cardiomyocytes derived from induced pluripotent stem cells with the DESE439K mutation were used as a model, Their abnormalities were compared with those observed in cardiac tissue samples obtained from … [Read more]
A focus on complex cases of autosomal dominant titinopathies
An international consortium of researchers coordinated by a team of geneticists from Montpellier and including researchers and clinicians from the Institute is reporting the clinical and biological data of patients diagnosed with primary titinopathy on the basis of more sophisticated investigations (including the RNA-seq technique): 17 patients corresponding to eight families were included in the … [Read more]
Expanding the phenotype of filamin-C-related myofibrillar myopathy
A tean of Danish researhers reports three patients with a rare filamin C myofibrillar myopathy. They present with atypical symptoms that expand the phenotype of filaminopathy. The new findings are progressive contractures of muscles surrounding the temporomandibular joint, detailed single myofiber histology findings and demonstration of severe affection of paraspinal muscles on MRI. Expanding … [Read more]
