Search results for "Charcot-Marie-Tooth"
showing 10 items of 37 documents
Assessment of Targeted Next-Generation Sequencing as a Tool for the Diagnosis of Charcot-Marie-Tooth Disease and Hereditary Motor Neuropathy
2016
Charcot-Marie-Tooth disease is characterized by broad genetic heterogeneity with >50 known disease-associated genes. Mutations in some of these genes can cause a pure motor form of hereditary motor neuropathy, the genetics of which are poorly characterized. We designed a panel comprising 56 genes associated with Charcot-Marie-Tooth disease/hereditary motor neuropathy. We validated this diagnostic tool by first testing 11 patients with pathological mutations. A cohort of 33 affected subjects was selected for this study. The DNAJB2 c.352+1G>A mutation was detected in two cases; novel changes and/or variants with low frequency (50 known disease-associated genes. Mutations in some of these gene…
The gene encoding ganglioside-induced differentiation-associated protein 1 is mutated in axonal Charcot-Marie-Tooth type 4A disease
2001
We identified three distinct mutations and six mutant alleles in GDAP1 in three families with axonal Charcot-Marie-Tooth (CMT) neuropathy and vocal cord paresis, which were previously linked to the CMT4A locus on chromosome 8q21.1. These results establish the molecular etiology of CMT4A (MIM 214400) and suggest that it may be associated with both axonal and demyelinating phenotypes.
Clinical spectrum of BICD2 mutations.
2020
Background and purpose Mutations in the BICD2 gene cause autosomal dominant lower extremity-predominant spinal muscular atrophy 2A (SMALED2A), a condition that is associated with a specific pattern of thigh and calf muscle involvement when studied by magnetic resonance imaging (MRI). Patients may present minor clinical sensory impairment, but objective sensory involvement has yet to be demonstrated. Methods We collected clinical data from 11 patients from five different families carrying mutations in BICD2. Genetic diagnosis was achieved using gene panel testing and skin biopsies were taken from two patients to study the epidermal nerve fiber density. Results In the studied patients, three …
Caracterización fenotípica y molecular de las neuropatías hereditarias en la infancia y la adolescencia
2022
ANTECEDENTES: La mayoría de las polineuropatías en la infancia son genéticamente determinadas, estimándose alrededor del 70-90% del total de neuropatías. Este grupo de neuropatías hereditarias (NH) comprende las NH tipo Charcot-Marie-Tooth y los síndromes hereditarios complejos bien sean enfermedades neurodegenerativas o errores innatos del metabolismo en los que la polineuropatía es una de sus características. La literatura médica es escasa en estudios de neuropatías hereditarias en población pediátrica, lo que puede ser atribuible a la escasez de programas nacionales e internacionales de bases de datos y escalas uniformes de evaluación pediátricas de aplicación generalizada. OBJETIVOS: El…
A Drosophila model of GDAP1 function reveals the involvement of insulin signalling in the mitochondria-dependent neuromuscular degeneration
2017
[EN] Charcot-Marie-Tooth disease is a rare peripheral neuropathy for which there is no specific treatment. Some forms of Charcot-Marie-Tooth are due to mutations in the GDAP1 gene. A striking feature of mutations in GDAP1 is that they have a variable clinical manifestation, according to disease onset and progression, histology and mode of inheritance. Studies in cellular and animal models have revealed a role of GDAP1 in mitochondrial morphology and distribution, calcium homeostasis and oxidative stress. To get a better understanding of the disease mechanism we have generated models of over-expression and RNA interference of the Drosophila Gdapl gene. In order to get an overview about the c…
Oxidative Stress, a Crossroad Between Rare Diseases and Neurodegeneration
2020
Oxidative stress is an imbalance between production and accumulation of oxygen reactive species and/or reactive nitrogen species in cells and tissues, and the capacity of detoxifying these products, using enzymatic and non-enzymatic components, such as glutathione. Oxidative stress plays roles in several pathological processes in the nervous system, such as neurotoxicity, neuroinflammation, ischemic stroke, and neurodegeneration. The concepts of oxidative stress and rare diseases were formulated in the eighties, and since then, the link between them has not stopped growing. The present review aims to expand knowledge in the pathological processes associated with oxidative stress underlying …
The Effect of a Novel c.820C>T (Arg274Trp) Mutation in the Mitofusin 2 Gene on Fibroblast Metabolism and Clinical Manifestation in a Patient
2017
Charcot-Marie-Tooth disease type 2A (CMT2A) is an autosomal dominant axonal peripheral neuropathy caused by mutations in the mitofusin 2 gene (MFN2). Mitofusin 2 is a GTPase protein present in the outer mitochondrial membrane and responsible for regulation of mitochondrial network architecture via the fusion of mitochondria. As that fusion process is known to be strongly dependent on the GTPase activity of mitofusin 2, it is postulated that the MFN2 mutation within the GTPase domain may lead to impaired GTPase activity, and in turn to mitochondrial dysfunction. The work described here has therefore sought to verify the effects of MFN2 mutation within its GTPase domain on mitochondrial and e…
Mitochondrial defects and neuromuscular degeneration caused by altered expression of Drosophila Gdap1: implications for the Charcot–Marie–Tooth neuro…
2014
One of the genes involved in Charcot-Marie-Tooth (CMT) disease, an inherited peripheral neuropathy, is GDAP1. In this work, we show that there is a true ortholog of this gene in Drosophila, which we have named Gdap1. By up- and down-regulation of Gdap1 in a tissue-specific manner, we show that altering its levels of expression produces changes in mitochondrial size, morphology and distribution, and neuronal and muscular degeneration. Interestingly, muscular degeneration is tissue-autonomous and not dependent on innervation. Metabolic analyses of our experimental genotypes suggest that alterations in oxidative stress are not a primary cause of the neuromuscular degeneration but a long-term c…
Complejidad genética y fisiopatología de neuropatías hereditarias sensitivo y/o motoras
2019
CAPÍTULO 1: “De la clínica a la mutación: Bases genéticas de neuropatías periféricas hereditarias” Las neuropatías periféricas hereditarias comprenden un grupo heterogéneo de enfermedades monogénicas degenerativas que afectan al sistema nervioso periférico y están producidas por mutaciones en más de 100 genes. El descubrimiento de nuevos genes y/o mutaciones es de vital importancia para comprender el mecanismo de enfermedad y con ello, lograr el desarrollo de estrategias terapéuticas. Mediante secuenciación de exoma, se han investigado las bases genéticas en cinco familias y hemos establecido la mutación causal en dos de ellas, atribuyendo un nuevo fenotipo clínico al gen KCNA1 y asociando …
Junctophilin-1 is a modifier gene of GDAP1-related Charcot-Marie-Tooth disease.
2014
Mutations in the GDAP1 gene cause different forms of Charcot-Marie-Tooth (CMT) disease, and the primary clinical expression of this disease is markedly variable in the dominant inheritance form (CMT type 2K; CMT2K), in which carriers of the GDAP1 p.R120W mutation can display a wide range of clinical severity. We investigated the JPH1 gene as a genetic modifier of clinical expression variability because junctophilin-1 (JPH1) is a good positional and functional candidate. We demonstrated that the JPH1-GDAP1 cluster forms a paralogon and is conserved in vertebrates. Moreover, both proteins play a role in Ca(2+) homeostasis, and we demonstrated that JPH1 is able to restore the store-operated Ca…