Who says humans aren’t the result of Darwinian evolution? This week, researchers report identifying some 1800 genes that appear to have been the target of natural selection. Some of the genes may be important in understanding the genetics behind disease as well as the evolution of the human brain.
Now a team of scientists at the University of California, Irvine, has used a new computational approach–the “linkage disequilibrium decay” test–to search for signs of selection over the entire human genome. As a rule, the greater the linkage disequilibrium associated with a gene, the more likely that the gene has been under recent selection. Harnessing data from two existing databases of human diversity, the team found some 1800 genes that appeared to have been under selection during the last 10,000 to 50,000 years. According to team leader and genome researcher Robert Moyzis, this is between 10 and 100 times greater than the number found in previous studies. The genes belong to several biologically important categories, including genes important in defense against disease, controlling the cell cycle, protein metabolism, and nervous system functioning, the researchers report online this week in Proceedings of the National Academy of Sciences.