Publication date: May 18, 2019
Findings from this new study were published recently in the American Journal of Human Genetics through an article titled -Length of Uninterrupted CAG, Independent of Polyglutamine Size, Results in Increased Somatic Instability, Hastening Onset of Huntington’s Disease. “
-Our study reveals that age of onset in Huntington’s disease is influenced not only by the length of the expansion mutation but also by the DNA sequence directly adjacent to this repetitive sequence,” said senior study investigator Michael Hayden, PhD, a professor of medical genetics and director emeritus for the CMMT, which is part of the faculty of medicine at UBC and located at BC Children’s.
While previous studies of the huntingtin gene have focused on the length of the string of glutamine building blocks in the DNA of the gene, this study examined variants in the DNA sequence encoding for these glutamine building blocks and the relationship between these variants and the age of onset of the disease.
The researchers screened samples from patients in the UBC Huntington’s disease biobank for the variant in the huntingtin gene, to examine the age of onset and whether the mutation was more likely to expand to longer repeat lengths in the blood.