Humans are keenly interested in their origins, and we now have more DNA information than ever to help us to reconstruct our genetic history. Two papers in Nature delve into the rapidly expanding databank to produce new nuggets of information.
Carlos Bustamante and colleagues combine large data sets for the American population to reveal that - for their sample at least - European-American populations have more potentially damaging mutations per variable DNA site than African-American populations. Given the large amount of data used, their discovery settles a debate about the number of these damaging mutations in human populations, and supports the idea that European-Americans as a whole, and not just specific isolated groups, went through a more recent population 'bottleneck' than did African-Americans.
Andrew Singleton, Noah Rosenberg and colleagues characterize more than 500,000 DNA markers in the human genome, using 485 volunteers from the Human Genome Diversity Project. They describe the extent of variations across 29 different populations, from Africa, through Europe and the Middle East, through central to South-East Asia, to Oceania and the Americas. Their data resolution is nearly two orders of magnitude greater than previous assessments of human populations and includes both single base changes and changes in larger chunks called copy-number variants. Comparison of these two types of genetic variation enables an increasingly accurate assessment of the complete structure of the human family tree.
Carlos Bustamante Cornell University, Ithaca, NY, USA)
Andrew Singleton (National Institute on Aging, Bethesda, MD, USA)
Noah Rosenberg (University of Michigan, Ann Arbor, MI, USA)
(C) Nature press release.
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