Susan JohnstonNew lab preprint by John McAuley: the genetic architecture of recombination rates is sexually-dimorphic and polygenic in wild house sparrows. What have we found…?
https://www.biorxiv.org/content/10.1101/2023.01.26.525019v2.article-info
We used pedigree and SNP data from the ✨amazing✨long-term study of house sparrows in Helgeland, Norway, to quantify recombination in gametes transmitted from parents to offspring. We examined two measures of recombination in >13,000 gametes from >2,600 birds, evenly balanced between males and females.
Recombination rates are heritable and “polygenic” (i.e. caused by many loci of small effect) in both sexes. Many of these appear to act in trans as global modification modifiers. And, females have ~1.4 more recombination than males. Interestingly, the sexes have a largely unshared genetic basis (rA ~ 0.3), meaning sex-specific rates have potential for independent evolution.
Birds have a maternally-inherited germline restricted chromosome (GRC) that is likely enriched for meiotic genes. Pedigree modelling shows that the GRC and W are unlikely to drive recombination rate *variation* in our case.
This is brief summary of a challenging phenotype and complicated analysis. We try to address issues in our approaches and discussion. We are happy for feedback and comments 😊🐦🧬