Yant, Levi
- Institutionen för växtbiologi, Sveriges lantbruksuniversitet
- University of Nottingham
- Univerzita Karlova
Sammanfattning
Genetic variation underpins evolutionary change, but mutation accumulation increasesgenetic load. Various factors affect the extent of load, such as population size andbreeding system, but other important determinants remain unexplored. In particular,whole- genome duplication (WGD)—a pervasive macromutation occurring broadlyacross Eukaryotes—remains poorly understood in terms of its impact on neutral andselective processes within populations. Using iterative forward simulations and empiricalanalysis of 632 short- and 16 long-read sequenced individuals of Arabidopsis arenosa (in23 diploid and 42 natural autotetraploid populations), we measure the effects of WGDon genome-wide diversity and mutation load. Our simulations show how genetic varia-tion gradually rises in autotetraploids due to increased mutational target size. Moreover,mutation load increases due to relaxed purifying selection as ploidies rise, when delete-rious mutations are masked by additional chromosome copies. Empirical data confirmthese patterns, showing significant increases in nucleotide diversity, ratios of nonsyn-onymous to synonymous SNPs, and numbers of indels and large structural variants inA. arenosa autotetraploids. However, a rather modest increase in load proxies togetherwith a broad distribution and niche of autotetraploids suggests load accumulation hasnot yet limited their successful expansion. Overall, we demonstrate a complex interplaybetween neutral processes and purifying selection in shaping genetic variation followingWGD and highlight ploidy as an important determinant of mutation load, geneticdiversity, and therefore adaptive potential in natural populations.
Nyckelord
Arabidopsis; evolution; genomics; genetic load; natural selection
Publicerad i
Proceedings of the National Academy of Sciences of the United States of America
2025, volym: 122, nummer: 31, artikelnummer: e2501739122
SLU författare
UKÄ forskningsämne
Evolutionsbiologi
Genetik och genomik
Publikationens identifierare
- DOI: https://doi.org/10.1073/pnas.2501739122
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/143228