Neandertals were lactose intolerant

An international group of scientists, led by Prof. Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology (Germany), has completed the first rough draft of Neandertal’s genetic instruction manual. Neandertals, the species Homo neanderthalensis, were appearing about 300,000 years ago and living in Europe and parts of Asia until going extinct about 30,000 years ago. Anatomically modern humans, the species known as Homo sapiens, first appeared in Africa about 250,000 to 200,000 years ago.

The team has decoded 3.7 billion bases of Neandertal DNA from a bone of a female Neandertal fossil discovered in Vindija cave in Croatia. That DNA represents about 63 percent of the total Neandertal genome. Analysis of the genome reveals that humans and Neandertals share genetic roots stretching back at least 830,000 years.

The genetic evidence suggests that humans and Neandertals are very similar(sharing between 99.5% to 99.9% of our DNA sequence), but that the two species probably didn’t interbreed. Also, most people in the world are unable to digest milk as adults (lactose intolerant). But a variant of the gene which encodes the lactase (enzyme that breaks down the sugar lactose in milk) is common in people of northern European descent. The researchers examined the lactase gene in Neandertals to see if that trait might have been passed from Neandertals to modern humans. But Neandertals have the lactose-intolerant version of the gene.The Neandertal was not able to drink milk after it was weaned.

Source : ScienceNews March 14th 2009

Date : 05.13.2009