Sex chromosomes in conflict

House mouse (by Wenfei Tong http://darwinsjackal.blogspot.com/)

House mouse (by Wenfei Tong)

Have you thought that not all the genes in your body might have the same evolutionary interests? The mouse Y chromosome has just been revealed after years of superhuman slog and turns out to be strikingly different from other non-recombining sex chromosomes in two main ways. Firstly, the mouse Y contains almost no DNA signatures of its past as a non sex chromosome. Secondly, most of it isn’t “junk”. Both these observations have shown just how much conflict within a genome can shape the evolution of entire chromosomes.

Figure from Sho et a. 2014, showing how much of the mouse Y contains recently evolved, repetitive coding sequences.

Figure from Sho et a. 2014, showing how much of the mouse Y contains recently evolved, repetitive coding sequences.

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