Sex Chromosome Specialization and Degeneration in Mammals

  title={Sex Chromosome Specialization and Degeneration in Mammals},
  author={Jennifer A. Marshall Graves},

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Gene dosage in the evolution and function of mammalian sex chromosomes

Evidence is reviewed that heteromorphic sex chromosomes evolved from an autosomal pair, and that one of the consequences of X–Y differentiation is the evolution of dosage compensation by X inactivation and upregulation of the active X, which in turn has selected for a highly conserved X chromosome.

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Far from being random and diverse, known human Y-chromosome genes show just a few distinct expression profiles, and their relative functional conformity reflects evolutionary factors inherent to sex-specific chromosomes.

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Evidence that recombination suppression occurs progressively in evolutionarily independent cases is reviewed, suggesting that selection drives loss of recombination over increasingly large regions.

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A new study in mice adds a missing piece of the puzzle: the composition of the X chromosome in mammals is influenced by inactivation of the sex chromosomes during male meiosis.

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The rise and fall of SRY.

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