According to David Page, “the Y chromosome is the Rodney Dangerfield of the human genome.” Regarded for 50 years as a genetic wasteland, the Y chromosome just doesn’t get any respect…until now. Page’s lab has made some startling discoveries that reverse the prevailing view.
Recall from basic biology that pairs of chromosomes exchange genetic material through a process of crossing over. This leads to genetic variation in offspring, and can weed out dangerous mutations. Although there’s limited gene swapping between the sex-determining X and Y chromosomes, the popular belief has been that a large portion of the Y could not recombine, and therefore will sooner or later self destruct. The long-term outlook for the Y chromosome was bleak.
But now there is hope and renewed respect for the Y. Page has found vast sequences of DNA on the Y that appear like palindromes (words like “mom” that read the same backwards and forwards). Page believes the two halves of the palindrome engage in a kind of crossing over. This can lead to repairing mutations, just as in ordinary chromosomes. Through this unique method, the Y chromosome not only endures but prevails.
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