Sequential Turnovers of Sex Chromosomes in African Clawed Frogs (Xenopus) Suggest Some Genomic Regions Are Good at Sex Determination.
Sexual differentiation is fundamentally important for reproduction, yet the genetic triggers of this developmental process can vary, even between closely related species. Recent studies have uncovered, for example, variation in the genetic triggers for sexual differentiation within and between species of African clawed frogs (genusXenopus). Here, we extend these discoveries by demonstrating that yet another sex determination system exists inXenopus, specifically in the speciesXenopus borealisThis system evolved recently in an ancestor ofX. borealisthat had the same sex determination system asX. laevis, a system which itself is newly evolved. Strikingly, the genomic region carrying the sex determination factor inX. borealisis homologous to that of therian mammals, including humans. Our results offer insights into how the genetic underpinnings of conserved phenotypes evolve, and suggest an important role for cooption of genetic building blocks with conserved developmental roles.
Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
Benjamin L S
BLS
Furman
Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada evansb@mcmaster.ca.
Ben J
BJ
Evans
Genetics of sex; SOX3; Xenopus; rapid evolution; sex chromosome turnover; sex chromosomes