A new look at the human Y chromosome has overturned longstanding ideas about its evolutionary history. Far from being in a state of decay, the Y chromosome is the fastest-changing part of the human genome and is constantly renewing itself. This is ‘a result as unexpected as it is stunning - truly amazing, said Scott Hawley, a chromosome expert at the Stowers Institute in Kansas City, Mo. The Y chromosome makes its owner male because it carries the male-determining gene. Boys are born with one Y and one X chromosome in all their body’s cells, while girls have two X’s. The other 22 pairs of chromosomes in which the human genome is packaged are the same in both sexes. The Y chromosome’s rapid rate of evolutionary change does not mean that men are evolving faster than women. But its furious innovation is likely to be having reverberations elsewhere in the human genome. The finding was reported online on Wednesday in the journal Nature by a team led by Jennifer Hughes and David Page of the Whitehead Institute in Cambridge, Mass. In 2003, Dr. Page, working with scientists at the Washington University School of Medicine, decoded the […]