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  • Interrogating the Roles of Mutation–Selection Balance, Heterozygote Advantage, and Linked Selection in Maintaining Recessive Lethal Variation in Natural Populations
Title: Interrogating the Roles of Mutation–Selection Balance, Heterozygote Advantage, and Linked Selection in Maintaining Recessive Lethal Variation in Natural Populations
For nearly a century, evolutionary biologists have observed chromosomes that cause lethality when made homozygous persisting at surprisingly high frequencies (>25%) in natural populations of many species. The evolutionary forces responsible for the maintenance of such detrimental mutations have been heavily debated—are some lethal mutations under balancing selection? We suggest that mutation–selection balance alone cannot explain lethal variation in nature and the possibility that other forces play a role. We review the potential that linked selection in particular may drive maintenance of lethal alleles through associative overdominance or linkage to beneficial mutations or by reducing effective population size. Over the past five decades, investigation into this mystery has tapered. During this time, key scientific advances have provided the ability to collect more accurate data and analyze them in new ways, making the underlying genetic bases and evolutionary forces of lethal alleles timely for study once more. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 11 is February 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.  more » « less
Award ID(s):
2019789
PAR ID:
10381994
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Annual Review of Animal Biosciences
Volume:
11
Issue:
1
ISSN:
2165-8102
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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