Major breakthrough for neuromuscular diseases diagnosis
Top : Results obtained with next generation sequencing, allowing a multiple reading of genetic information coded on the DNA with 4 letters (A, C, G and T). Human DNA is composed of 3 billion of letters and a change on one of them can lead to a genetic disorder. At the bottom are the results of the former method with only one reading available.
Acta Neuropathol Aug 2012
April 21, 2012
Current diagnostic approaches for neuromuscular diseases are time-consuming. Jocelyn Laporte team has developed with clinicians a particularly efficient strategy for genetic diagnosis of these disorders. These results are published on April 21th 2012 in Acta Neuropathologica.
Neuromuscular diseases gather myopathies and neuropathies (Charcot-Marie-Tooth disease, spinal muscular atrophy, Amyotrophic lateral sclerosis, ataxias, etc.). They are a group of genetic diseases often leading to severe chronic invalidity. There are more than 200 neuromuscular disorders with a total incidence exceeding 1 in 3,000 in the world. Despite tremendous efforts made in research on these pathologies, their diagnosis is currently time-consuming and expensive, since many genes can be involved. The identification of the mutated gene in each patient needs a deep examination of symptoms, completed by a gene-by-gene analysis. Eventually, genetic causes still remain unknown for approximately half of the patients.
For two years, Jocelyn Laporte team has worked with IGBMC platforms of deep sequencing and bioinformatics to set up an efficient diagnosis strategy. Instead of the usual gene-by-gene analysis, they used next generation sequencing to test simultaneously all genes related to these pathologies (267 genes). Thanks to collaborations with Strasbourg and Hautepierre hospitals, this method has been tested successfully on patients, providing a first proof-of-principle of its efficiency.
“While some patients had waited for a diagnosis for more than 2 years, this method has provided results in only two months!” Jocelyn Laporte explains. This method enabled to widen the panel of diagnosed patients. Faster and cheaper, it will result in a more adapted medical care. The precise knowledge of mutations involved in these disorders will give an access to better genetic counseling and more targeted therapeutic approaches.