Origins and functional evolution of Y chromosomes across mammals

  title={Origins and functional evolution of Y chromosomes across mammals},
  author={Diego Cortez and Ray Marin and Deborah Toledo-Flores and Laure Froidevaux and Ang{\'e}lica Liechti and Paul D. Waters and Frank Gr{\"u}tzner and Henrik Kaessmann},
Y chromosomes underlie sex determination in mammals, but their repeat-rich nature has hampered sequencing and associated evolutionary studies. Here we trace Y evolution across 15 representative mammals on the basis of high-throughput genome and transcriptome sequencing. We uncover three independent sex chromosome originations in mammals and birds (the outgroup). The original placental and marsupial (therian) Y, containing the sex-determining gene SRY, emerged in the therian ancestor… 

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Did sex chromosome turnover promote divergence of the major mammal groups?

  • J. Graves
  • Biology
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2016
It is proposed that the evolution of therian mammals was precipitated by evolution of a male‐determining SRY gene, defining a novel XY sex chromosome pair, and interposing a reproductive barrier with the ancestral population of synapsid reptiles 190 million years ago (MYA).

Repeated sex chromosome evolution in vertebrates supported by expanded avian sex chromosomes

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Evolutionary conservation of Y Chromosome ampliconic gene families despite extensive structural variation

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Extinction of chromosomes due to specialization is a universal occurrence

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The Gene Content of Mammalian and Avian Sex Chromosomes

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Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content

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No Evidence for a Second Evolutionary Stratum during the Early Evolution of Mammalian Sex Chromosomes

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It is reported that DAZ arrived on the Y chromosome about 38 million years ago via the transposition of at least 1.1 megabases of autosomal DNA, but all five genes were subsequently lost through mutation or deletion.