Studies of Y Chromosome evolution have focused primarily on gene decay, a consequence of suppression of crossing-over with the X Chromosome. Here, we provide evidence that suppression of X–Y crossing-over unleashed a second dynamic: selfish X–Y arms races that reshaped the sex chromosomes in mammals as different as cattle, mice, and men. Using super-resolution sequencing, we explore the Y Chromosome of Bos taurus (bull) and find it to be dominated by massive, lineage-specific amplification of testis-expressed gene families, making it the most gene-dense Y Chromosome sequenced to date. As in mice, an X-linked homolog of a bull Y-amplified gene has become testis-specific and amplified. This evolutionary convergence implies that lineage-specific X–Y coevolution through gene amplification, and the selfish forces underlying this phenomenon, were dominatingly powerful among diverse mammalian lineages. Together with Y gene decay, X–Y arms races molded mammalian sex chromosomes and influenced the course of mammalian evolution.

中文翻译：

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Bos taurus 的序列分析揭示了哺乳动物谱系中 X-Y 军备竞赛的普遍性

Y 染色体进化的研究主要集中在基因衰变上，这是抑制与 X 染色体交叉的结果。在这里，我们提供的证据表明，抑制 X-Y 交叉释放了第二个动力：自私的 X-Y 军备竞赛重塑了与牛、小鼠和男性一样不同的哺乳动物的性染色体。使用超分辨率测序，我们探索Bos taurus的 Y 染色体（公牛）并发现它以睾丸表达基因家族的大规模谱系特异性扩增为主，使其成为迄今为止测序的基因最密集的 Y 染色体。与小鼠一样，公牛 Y 扩增基因的 X 连锁同源物已成为睾丸特异性并扩增。这种进化趋同意味着通过基因扩增的谱系特异性 X-Y 共同进化，以及这种现象背后的自私力量，在不同的哺乳动物谱系中占主导地位。与 Y 基因衰变一起，X-Y 军备竞赛塑造了哺乳动物的性染色体并影响了哺乳动物的进化过程。