These findings are expected to help researchers understand the roots of congenital conditions that occur more often in African Americans (due to mutations at hotspots that are more common in African Americans), and also to help discover new disease genes in all populations, because of the ability to map these genes more precisely.
The new map is so accurate because African American individuals often have a mixture of African and European ancestry from over the last two hundred years. David Reich and Simon Myers are experts in analyzing genetic data to reconstruct the mosaic of regions of African and European genetic ancestry in DNA of African Americans. By applying a computer program they previously wrote, Anjali Hinch identified the places in the genomes where the African and European ancestry switches in almost 30,000 people, detecting about 70 switches per person. These areas corresponded to recombination events in the last few hundred years. Thus, the researchers identified more than two million recombination events that they used to build the map.
The study was only possible because of collaboration from 81 co-authors, using DNA samples from five large studies that have been carried out to study common diseases such as heart disease and cancer, funded by the National Institutes of Health, the Department of Defense, and many private foundations.
Said James Wilson, a professor at the University of Mississippi Medical Center who was responsible for coordinating the collaboration, "All the co-authors worked together in an incredibly collegial way to put together the enormous set of samples and high quality genetic data that made this study a success."
|Contact: David Cameron|
Harvard Medical School