
Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(44)
Published: Oct. 22, 2024
The dominance of beneficial mutations is a key evolutionary parameter affecting the rate and genetic basis adaptation, yet it notoriously difficult to estimate. A leading method infer compare relative rates adaptive substitution for X-linked autosomal genes, which—according classic model by Charlesworth et al. (1987)—is simple function new mutations. Recent evidence that are faster genes implies, accordingly, usually recessive. However, this conclusion incompatible with theories dominance, which predict tend be dominant or overdominant respect fitness. To address incompatibility, we use Fisher’s geometric distribution fitness effects positively selected on X autosomes. Previous predictions faster-X theory emerge as special case our in phenotypic small distance optimum. But mutational become large optimum, observe an elevated tempo substitutions autosomes across broader range conditions, including those predicted dominance. Our results imply that, contrary previous models, can plausibly generate patterns adaptation. We discuss resulting implications genomic studies adaptation inferences
Language: Английский