Study dispels theories of Y chromosome’s demise: Stripped-down chromosome retains key genes for fertility

Population geneticists compared the Y chromosomes of eight African and eight European men to understand why the chromosome is so puny. They attribute the size to strong natural selection to remove harmful genes — so-called purifying selection — but find essential roles for the remaining genes, dispelling the common notion that the Y’s genes are mostly unimportant and that the chromosome is destined to dwindle and disappear.
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Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/top_science/~3/grIAt68_IRM/140109175736.htm