Le syndrome de Schwartz-Jampel Urtizberea, J. Andoni; Severa, Gianmarco; Ropars, Juliette ...
M.S. Médecine sciences,
11/2023, Letnik:
39
Journal Article
Recenzirano
Le syndrome de Schwartz-Jampel (SJS, OMIM #255800) est une affection génétique ultra-rare définie par des manifestations myotoniques et des anomalies ostéo-articulaires. Transmis selon un mode ...autosomique récessif, sa prévalence est plus élevée dans les zones de forte endogamie. La découverte du gène
HSPG2
codant une protéine de la lame basale a permis de mieux en délimiter les contours nosologiques. Le diagnostic est généralement très fortement suspecté cliniquement puis confirmé en biologie moléculaire. Le traitement reste à ce jour essentiellement symptomatique.
The Schwartz-Jampel syndrome (SJS, OMIM #255800) is an ultra-rare genetic disease characterized by myotonic manifestations combined with bone and cartilage abnormalities. Following an autosomal recessive mode of inheritance, its prevalence is more significant in highly-inbred areas. The unraveling of the
HSPG2
gene encoding a protein of the basal lamina enabled a better nosological delineation of the syndrome. The diagnosis is usually strongly suspected at the clinical level and then confirmed by molecular biology. To date, the treatment remains essentially symptomatic.
Gene therapies in pediatrics Andoni Urtizberea, J.
Archives de pédiatrie : organe officiel de la Société française de pédiatrie,
11/2023, Letnik:
30, Številka:
8
Journal Article
Brown-Vialetto-Van Laere syndrome was first described in 1894 as a rare neurodegenerative disorder characterized by progressive sensorineural deafness in combination with childhood amyotrophic ...lateral sclerosis. Mutations in the gene, SLC52A3 (formerly C20orf54), one of three known riboflavin transporter genes, have recently been shown to underlie a number of severe cases of Brown-Vialetto-Van Laere syndrome; however, cases and families with this disease exist that do not appear to be caused by SLC52A3 mutations. We used a combination of linkage and exome sequencing to identify the disease causing mutation in an extended Lebanese Brown-Vialetto-Van Laere kindred, whose affected members were negative for SLC52A3 mutations. We identified a novel mutation in a second member of the riboflavin transporter gene family (gene symbol: SLC52A2) as the cause of disease in this family. The same mutation was identified in one additional subject, from 44 screened. Within this group of 44 patients, we also identified two additional cases with SLC52A3 mutations, but none with mutations in the remaining member of this gene family, SLC52A1. We believe this strongly supports the notion that defective riboflavin transport plays an important role in Brown-Vialetto-Van Laere syndrome. Initial work has indicated that patients with SLC52A3 defects respond to riboflavin treatment clinically and biochemically. Clearly, this makes an excellent candidate therapy for the SLC52A2 mutation-positive patients identified here. Initial riboflavin treatment of one of these patients shows promising results.
Distal hereditary motor neuropathies are a rare subgroup of inherited peripheral neuropathies hallmarked by a length-dependent axonal degeneration of lower motor neurons without significant ...involvement of sensory neurons. We identified patients with heterozygous nonsense mutations in the αII-spectrin gene, SPTAN1, in three separate dominant hereditary motor neuropathy families via next-generation sequencing. Variable penetrance was noted for these mutations in two of three families, and phenotype severity differs greatly between patients. The mutant mRNA containing nonsense mutations is broken down by nonsense-mediated decay and leads to reduced protein levels in patient cells. Previously, dominant-negative αII-spectrin gene mutations were described as causal in a spectrum of epilepsy phenotypes.