UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Haploid Selection Favours Suppressed Recombination Between Sex Chromosomes Despite Causing Biased Sex Ratios

Scott, MF; Otto, SP; (2017) Haploid Selection Favours Suppressed Recombination Between Sex Chromosomes Despite Causing Biased Sex Ratios. Genetics , 207 (4) pp. 1631-1649. 10.1534/genetics.117.300062.

[thumbnail of Early_view_Genetics_MFS_SPO.pdf] Text
Early_view_Genetics_MFS_SPO.pdf - Accepted Version
Access restricted to UCL open access staff

Download (2MB)

Abstract

To date, research on the evolution of sex chromosomes has focused on sexually antagonistic selection among diploids, which has been shown to be a potent driver of the strata and reduced recombination that characterize many sex chromosomes. However, significant selection can also occur on haploid genotypes during less conspicuous life cycle stages, e.g., competition among sperm/pollen or meiotic drive during gamete/spore production. These haploid selective processes are typically sex-specific, e.g., gametic/gametophytic competition typically occurs among sperm/pollen and meiotic drive typically occurs during either spermatogenesis or oogenesis. We use models to investigate whether sex-specific selection on haploids could drive the evolution of recombination suppression on the sex chromosomes, as has been demonstrated for sex-specific selection among diploids. A potential complication is that zygotic sex-ratios become biased when haploid selected loci become linked to the sex-determining region because the zygotic sex ratio is determined by the relative number and fitness of X- versus Y-bearing sperm. Despite causing biased zygotic sex-ratios, we find that a period of sex-specific haploid selection generally favours recombination suppression on the sex chromosomes.Suppressed recombination is favoured because it allows associations to build up between haploid-beneficial alleles and the sex that experiences haploid selection most often (e.g., pollen beneficial alleles become strongly associated with the male determining region, Y or Z). Haploid selected loci can favour recombination suppression even in the absence of selective differences between male and female diploids. Overall, we expand our view of the sex-specific life cycle stages that can drive sex chromosome evolution to include gametic competition and meiotic drive. Based on our models, sex chromosomes should become enriched for genes that experience haploid selection, as is expected for genes that experience sexually antagonistic selection. Thus, we generate a number of promising predictions that can be evaluated in emerging sex chromosome systems.

Type: Article
Title: Haploid Selection Favours Suppressed Recombination Between Sex Chromosomes Despite Causing Biased Sex Ratios
Location: United States
DOI: 10.1534/genetics.117.300062
Publisher version: https://doi.org/10.1534/genetics.117.300062
Language: English
Keywords: meiotic drive, pollen competition, recombination evolution, sex chromosomes, sex ratio, sperm competition
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences > Genetics, Evolution and Environment
URI: https://discovery.ucl.ac.uk/id/eprint/10039689
Downloads since deposit
1Download
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item