What makes people different? A working map of regions of genetic variation across the human genome is reported online in Nature.
Everybody gets two copies of their DNA - one from each parent - but some regions can be duplicated or deleted, which gives rise to 'copy number variation' within the population. Matthew Hurles, Stephen Scherer and colleagues have made a comprehensive map of CNVs in the human genome from 450 individuals of European, African or East Asian ancestry.
The team identify 30 places in the genome that are candidates for influencing human disease susceptibility, including 3 CNVs that have already been linked with disease in genome-wide association studies. Importantly, the authors conclude that CNVs are unlikely to explain much of the dark matter of the genome - the heritability unexplained by SNPs.
The findings also shed light on how this type of genetic variation is introduced to the genome, providing insights into selective forces that act on CNVs and mechanisms that generate them. In a related News & Views article, John Armour predicts that the study "will become the working first-line resource for reliable data on copy number variation for future studies of human variation, genome evolution and disease genetics."
Matthew Hurles (Wellcome Trust Sanger Institute, Cambridge, UK)
Stephen Scherer (The Hospital for Sick Children, Toronto, Canada)
Abstract available online.
(C) Nature press release.
Message posted by: Trevor M. D'Souza