To verify these observations, the scientists created a tailor-made chromosome 21; their analyses revealed two areas of variability in the number of copies of a gene (or CNV), and one area identified by a nucleotide polymorphism (or SNP), which can be associated with the risk of heart deficiency. Therefore, this study highlights the role of two CNVs and one SNP in the cardiac pathogenesis of people with Down syndrome for the first time, revealing the genetic complexity of a common symptom of trisomy 21.
For the geneticist-authors of this study, the genetic architecture of the risk of congenital heart disease in individuals with Down syndrome must henceforth be understood as a complex combination, revealing the 21st chromosome, nucleotide polymorphism, and variability in the number of copies of a gene all at once; three factors to which we must add to the rest of the genome a still unidentified genetic variation, which Professor Antonarakis' group is already tracking.
and also the risk of chronic myeloid leukemia
In parallel, this same group has made progress in understanding another relatively common symptom of Down syndrome, by tracking the genetic variations that identify chronic myeloid leukemia in the body's cells.
This research is itself the subject of a publication in the latest issue of the online journal Blood; like the former, it contributes to the diagnostic and therapeutic improvement of major and misunderstood disorders, pathologies that are more successfully studied in people with trisomy 21, pathologies that can affect everyone.
|Contact: Stylianos Antonarakis|
Universit de Genve