Genomic Vision, DNA molecular combing specialist that develops tests for the diagnostics market and tools for the life sciences research market, has presented, at the Annual Meeting of the American Society of Human Genetics, the initial results of the pilot study undertaken with Quest Diagnostics that aims to identify a biomarker to improve genetic counseling for Spinal Muscular Atrophy (SMA) in the African-American population.
Genomic Vision said that the SMA is a hereditary genetic disease caused by a defect of the SMN1 gene in both of the patients’ copies of chromosome 5. The disease is transmitted in an autosomal recessive manner, which means that the healthy parents of an affected child carry the SMN1 gene defect, although they are completely asymptomatic. The frequency of healthy carriers of this disease in the general population is 1/40 to 1/60. The high incidence of this disease, and its severity, are the reasons why there is a strong demand for genetic counseling.
Due to the particularly complex genomic organization of the SMN locus, around 8% of individuals globally and 30% of healthy carriers in the African-American population cannot be detected efficiently using traditional molecular biology techniques. Detecting these healthy carriers is therefore crucial to improving genetic counseling among this population, explained Genomic Vision.
The poster presented during the annual meeting (entitled Molecular Combing reveals structural variations in the Spinal Muscular Atrophy locus in African-American population, session: Molecular and Cytogenetic Diagnostics) concerned the accurate mapping of the SMN locus in the African-American population using molecular combing technology.
Anne Jacquet, Director of Biomedical Research at Genomic Vision, comments: “The SMN locus is a very complex region that no technology has yet been able to accurately characterize. The initial results obtained with molecular combing using a specific Genomic Morse Code for the studied SMN region has revealed a more complex and variable genomic organization than that described in human genome sequencing databases. We have notably identified, at various points along the SMN locus, variable numbers of copies of the gene within a same individual and from one individual to another. This more accurate mapping of the SMN locus should provide us with crucial information for developing our screening test for healthy carriers, notably for the African-American population within which 30% of healthy carriers are currently not efficiently detected that is thus a real problem for providing families with genetic counseling.”