Evidence of still-ongoing convergence evolution of the lactase persistence T-13910 alleles in humans makes the case for a common Eurasian group of lactase persistence alleles across Eurasia, and among some African populations, derived from one mutational event within the last 10,000 years. A novel polymorphism associated with lactose tolerance in Africa: multiple causes for lactase persistence? points to other possible evolutionary events. The use of the term Africa is somewhat deceptive, these other alleles are found in groups like the Bedouin Arabs. One assumes that with the long history of agriculture in the Middle East these local alleles would have been relatively ancient as well. Why didn't they spread north as agriculture spread? And why didn't they spread east with agriculture? More of a question at this point.

Labels: Genetics, Human Evolution