Mastodawn

Susan Johnston Jul 8, 2024

🧬 New recombination review 🧬
Genetic variation is essential for evolution. So what do we know about genetic variation underlying recombination rates & distribution? I've written a perspective for MBE on why its important, what we have learned, & open questions for the future.

https://academic.oup.com/mbe/article/41/7/msae112/7705493?login=false

#recombination #meiosis #meiosis4eva

Understanding the Genetic Basis of Variation in Meiotic Recombination: Past, Present, and Future

Abstract. Meiotic recombination is a fundamental feature of sexually reproducing species. It is often required for proper chromosome segregation and plays

OUP Academic

Susan Johnston Jun 25, 2024

New lab preprint: GWAS on crossover dynamics in pigs led by Cathrine Brekke. We explored individual variation in rate, positioning and interference and found a few significant loci in females🐷:

📈👯‍♀️ Rate & interference associated with RNF212 (+ small rate effects at CTCF & REC114/REC8/CCNB1IP1)

📌 Broad-scale positioning at MEI4, SYCP2, PRDM9 (+ small effects at ZCWPW1 & ZCWPW2)

#meiosis #pigs #GWAS #recombination #meiosis4eva

https://biologists.social/@biorxivpreprint/112673500288980099

bioRxiv (@[email protected])

Individual variation in meiotic crossover positioning, rate and interference are driven by distinct genetic processes in domestic pigs. https://www.biorxiv.org/content/10.1101/2024.06.20.599484v1?med=mas

biologists.social

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Susan Johnston Mar 21, 2024

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 😊🐦🧬

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Susan Johnston Mar 21, 2024

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.

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Susan Johnston Mar 21, 2024

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.

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Susan Johnston Mar 21, 2024

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.

Susan Johnston Mar 21, 2024

New 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

Susan Johnston Dec 14, 2023

Are you a non-UK student looking for a PhD in evolutionary genetics? Our lab in Edinburgh is seeking applicants to investigate landscapes of recombination in wild mammals and birds 🦄🐦. More info in link 👇please get in touch ASAP. (Image: Tilly Scott)

https://docs.google.com/document/d/1vj7lFALNB3Fd-KT_GgVupqOvqtCr8rnrOybRir-ce88/edit?usp=sharing

2024 Darwin Trust PhD

Google Docs

Susan Johnston Sep 22, 2023

thomas lenormand Sep 22, 2023

Sex Unfolded Jacques Monod Conference. Third Edition in incredibly sunny Roscoff. Already 1 week ago. Thanks to all the participants! Many new ideas for the #evolutionofsex #recombination, #SexChromosomes #asexuality #evobio #popgen. 4th edition in 5 years by @KarineDoninck and Sylvain Glémin !

Susan Johnston Jun 12, 2023

Another 🐟🧬 collab with Cathrine Brekke & colleagues on individual meiotic crossover rates in Atlantic salmon. Females have 1.6x more COs but 8x more allelic "shuffling" on chromosomes than males, due to extreme sex-differences in CO landscape. Both measures are ~heritable and polygenic.

http://biorxiv.org/cgi/content/short/2023.06.07.543993v1?rss=1