In my collection The Birds the bees and the platypuses, I have included articles about the chimp genome (as compared to our own, of course) and the confusing hall of mirrors that is the human Y chromosome. Now, released online in Nature last week, the missing link has also been brought to book: the Y chromosome of the common chimp.
Surprisingly (but then again, not that surprisingly), the chimp's Y chromosome is massively more different from ours than the rest of the genome. Rapid change in the Y chromosome is easily explained by the fact that -- unlike all other chromosomes -- it doesn't have a matching partner that can serve as a quality control and backup copy. While it has evolved its own internal control mechanisms, which are responsible for the large number of repeats and mirrored sequences seen in the Y, this still means that it is much more vulnerable to mutation.
The news item in the current print issue of Nature tries to put a positive spin on it, saying it evolves faster. Well, it certainly changes faster, but not always for the better. There is a school of thinking saying that it decays and is on the way out in the long term. Lucky that our species will self-destruct before that time anyway.
Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content
Jennifer F. Hughes, Helen Skaletsky, Tatyana Pyntikova, Tina A. Graves, Saskia K. M. van Daalen, Patrick J. Minx, Robert S. Fulton, Sean D. McGrath, Devin P. Locke, Cynthia Friedman, Barbara J. Trask, Elaine R. Mardis, Wesley C. Warren, Sjoerd Repping, Steve Rozen, Richard K. Wilson & David C. Page