Strong selective sweeps associated with ampliconic regions in great ape X chromosomes

TY - JOUR

T1 - Strong selective sweeps associated with ampliconic regions in great ape X chromosomes

AU - Nam, Kiwoong

AU - Munch, Kasper

AU - Hobolth, Asger

AU - Y. Dutheil, Julien

AU - Veeramah, Krishna

AU - Woerner, August

AU - F. Hammer, Michael

AU - Ape Genome Diversity Project, Great

AU - Mailund, Thomas

AU - H. Schierup, Mikkel

N1 - This the resubmitted version, with supplementary

PY - 2014/2/24

Y1 - 2014/2/24

N2 - The unique inheritance pattern of X chromosomes makes them preferential targets of adaptive evolution. We here investigate natural selection on the X chromosome in all species of great apes. We find that diversity is more strongly reduced around genes on the X compared with autosomes, and that a higher proportion of substitutions results from positive selection. Strikingly, the X exhibits several megabase long regions where diversity is reduced more than five fold. These regions overlap significantly among species, and have a higher singleton proportion, population differentiation, and nonsynonymous to synonymous substitution ratio. We rule out background selection and soft selective sweeps as explanations for these observations, and conclude that several strong selective sweeps have occurred independently in similar regions in several species. Since these regions are strongly associated with ampliconic sequences we propose that intra-genomic conflict between the X and the Y chromosomes is a major driver of X chromosome evolution.

AB - The unique inheritance pattern of X chromosomes makes them preferential targets of adaptive evolution. We here investigate natural selection on the X chromosome in all species of great apes. We find that diversity is more strongly reduced around genes on the X compared with autosomes, and that a higher proportion of substitutions results from positive selection. Strikingly, the X exhibits several megabase long regions where diversity is reduced more than five fold. These regions overlap significantly among species, and have a higher singleton proportion, population differentiation, and nonsynonymous to synonymous substitution ratio. We rule out background selection and soft selective sweeps as explanations for these observations, and conclude that several strong selective sweeps have occurred independently in similar regions in several species. Since these regions are strongly associated with ampliconic sequences we propose that intra-genomic conflict between the X and the Y chromosomes is a major driver of X chromosome evolution.

KW - q-bio.PE

M3 - Journal article

JO - arXiv

JF - arXiv

ER -