PT  - JOURNAL ARTICLE
AU  - Tom van der Valk
AU  - Marc de Manuel
AU  - Tomas Marques-Bonet
AU  - Katerina Guschanski
TI  - Estimates of genetic load in small populations suggest extensive purging of deleterious alleles
AID  - 10.1101/696831
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 696831
4099  - http://biorxiv.org/content/early/2019/07/09/696831.short
4100  - http://biorxiv.org/content/early/2019/07/09/696831.full
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.