Genetic mutations in East Africans that are associated with the ability to digest milk as adults have been identified. The study of DNA found that the mutations evolved at the time in history when some Africans were beginning to raise cattle and evolved independently of the mutation that regulates milk digestion in Europeans.
The study was led by University of Maryland researcher Sarah Tishkoff, associate professor of biology and will be reported in the December 18, 2006 issue of Nature Genetics. The findings are not only evidence of how genes and culture co-evolve, says Tishkoff "they reveal one of the most striking genetic footprints of natural selection ever observed in humans."
The mutation in East African’s has gone undetected until now because it appears to be in a different location than the European mutation, and appears to be restricted to East African populations that herd cattle.