Primate evolution moves into the fast lane

The pace of evolution typically is measured in millions of years, as random mutations accumulate over generations. Researchers at Cornell and Bar-Ilan universities have uncovered a new mechanism for mutation in primates that is rare but rapid, site-specific and aggressive. The novel process is triggered by a member of the APOBEC family of virus-fighting enzymes. APOBECs in primate cells - including those of chimpanzees, Neanderthals and modern humans - mount a vigorous defense against viruses, bombarding the viral genome with clusters of mutations to thwart the infection. However, having a mutation-based defense is risky for cells, since "friendly fire" could wreak havoc on the genome as well. Alon Keinan , associate professor of biological statistics and computational biology at Cornell, collaborated with Erez Levanon at Bar-Ilan University in Israel to find the signature of past mutations in humans and our closest relatives. Their paper was published April 7 in the journal Genome Research.