A role for a neo-sex chromosome in stickleback speciation

Academic Article

Abstract

  • Sexual antagonism, or conflict between the sexes, has been proposed as a driving force in both sex-chromosome turnover and speciation. Although closely related species often have different sex-chromosome systems, it is unknown whether sex-chromosome turnover contributes to the evolution of reproductive isolation between species. Here we show that a newly evolved sex chromosome contains genes that contribute to speciation in threespine stickleback fish (Gasterosteus aculeatus). We first identified a neo-sex chromosome system found only in one member of a sympatric species pair in Japan. We then performed genetic linkage mapping of male-specific traits important for reproductive isolation between the Japanese species pair. The neo-X chromosome contains loci for male courtship display traits that contribute to behavioural isolation, whereas the ancestral X chromosome contains loci for both behavioural isolation and hybrid male sterility. Our work not only provides strong evidence for a large X-effect on reproductive isolation in a vertebrate system, but also provides direct evidence that a young neo-X chromosome contributes to reproductive isolation between closely related species. Our data indicate that sex-chromosome turnover might have a greater role in speciation than was previously appreciated. ©2009 Macmillan Publishers Limited. All rights reserved.
  • Published In

  • Nature  Journal
  • Digital Object Identifier (doi)

    Pubmed Id

  • 23787800
  • Author List

  • Kitano J; Ross JA; Mori S; Kume M; Jones FC; Chan YF; Absher DM; Grimwood J; Schmutz J; Myers RM
  • Start Page

  • 1079
  • End Page

  • 1083
  • Volume

  • 461
  • Issue

  • 7267