The Y Chromosome: think of it as the much-maligned medgadget that makes men… men. We know it’s shriveled and doesn’t do too much, but we’re pretty fond of it (Y is pictured, at the far right, next to the more robust X).
Via Wired, there’s a controversy among geneticists whether Y, ever the typical male, is even going to stick around:
The Y appeared 300 million years ago and has since eroded into a dinky chromosome because it lacks the mechanism other chromosomes have to get rid of damaged DNA. As a result, mutations have disabled hundreds of its original genes, causing them to be shed as useless. The Y now contains only 27 genes or families of virtually identical genes.
In 2003, [the Whitehead Institute’s Interim Director, Dr. David Page] reported that the modern-day Y has an unusual mechanism to fix about half of its genes and protect them from disappearing…
Jennifer A. Marshall Graves of the Australian National University in Canberra, a gene researcher who argues for eventual extinction of the Y chromosome, called Page’s work “beautiful” but said it didn’t shake her conviction that the Y is doomed…
The Y chromosome has already disappeared in some other animals and “there’s no reason to expect it can’t happen to humans,” she said. If it happened in people, some other chromosome would probably take over the sex-determining role of the Y, she said.
More from Dr. David Page’s web page.