Rainfall-driven sex-ratio genes in African buffalo suggested by correlations between Y-chromosomal haplotype frequencies and foetal sex ratio

W.F. van Hooft, H.H.T. Prins, W.M. Getz, A.E. Jolles, S.E. van Wieren, B.J. Greyling, P.D. Helden, A.D.S. Bastos

Research output: Contribution to journalArticleAcademicpeer-review

10 Citations (Scopus)

Abstract

Background - The Y-chromosomal diversity in the African buffalo (Syncerus caffer) population of Kruger National Park (KNP) is characterized by rainfall-driven haplotype frequency shifts between year cohorts. Stable Y-chromosomal polymorphism is difficult to reconcile with haplotype frequency variations without assuming frequency-dependent selection or specific interactions in the population dynamics of X- and Y-chromosomal genes, since otherwise the fittest haplotype would inevitably sweep to fixation. Stable Y-chromosomal polymorphism due one of these factors only seems possible when there are Y-chromosomal distorters of an equal sex ratio, which act by negatively affecting X-gametes, or Y-chromosomal suppressors of a female-biased sex ratio. These sex-ratio (SR) genes modify (suppress) gamete transmission in their own favour at a fitness cost, allowing for stable polymorphism. Results - Here we show temporal correlations between Y-chromosomal haplotype frequencies and foetal sex ratios in the KNP buffalo population, suggesting SR genes. Frequencies varied by a factor of five; too high to be alternatively explained by Y-chromosomal effects on pregnancy loss. Sex ratios were male-biased during wet and female-biased during dry periods (male proportion: 0.47-0.53), seasonally and annually. Both wet and dry periods were associated with a specific haplotype indicating a SR distorter and SR suppressor, respectively. Conclusions - The distinctive properties suggested for explaining Y-chromosomal polymorphism in African buffalo may not be restricted to this species alone. SR genes may play a broader and largely overlooked role in mammalian sex-ratio variation
Original languageEnglish
Article number106
Number of pages11
JournalBMC Evolutionary Biology
Volume10
DOIs
Publication statusPublished - 2010

Keywords

  • cattle bos-taurus
  • syncerus-caffer
  • male-fertility
  • meiotic drive
  • bovine tuberculosis
  • drosophila-melanogaster
  • microsatellite analysis
  • natural-populations
  • sperm
  • selection

Fingerprint Dive into the research topics of 'Rainfall-driven sex-ratio genes in African buffalo suggested by correlations between Y-chromosomal haplotype frequencies and foetal sex ratio'. Together they form a unique fingerprint.

  • Cite this