RT Journal Article
SR Electronic
T1 Estimates of genetic load in small populations suggest extensive purging of deleterious alleles
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 696831
DO 10.1101/696831
A1 Tom van der Valk
A1 Marc de Manuel
A1 Tomas Marques-Bonet
A1 Katerina Guschanski
YR 2019
UL http://biorxiv.org/content/early/2019/07/09/696831.abstract
AB Declining populations are expected to experience negative genetic consequences of inbreeding, which over time can drive them to extinction. Yet, many species have survived in small populations for thousands of generations without apparent fitness effects, possibly due to genetic purging of partially deleterious recessive alleles in inbred populations. We estimate the abundance of deleterious alleles in a range of mammals and find that conversely to current conservation thinking species with historically small population size and low genetic diversity generally have lower genetic load compared to species with large population sizes. Rapid population declines will thus disproportionally affect species with high diversity, as they carry many deleterious alleles that can reach fixation before being removed by genetic purging.