Mountain gorilla genomes reveal the impact of long-term population decline and inbreeding.

Publication Type:

Journal Article

Source:

Science (New York, N.Y.), Volume 348, Issue 6231, p.242-5 (2015)

Keywords:

Adaptation, Physiological, Animals, Biological Evolution, Democratic Republic of the Congo, DNA Copy Number Variations, Endangered Species, Female, Genetic Variation, GENOME, Gorilla gorilla, Homozygote, Inbreeding, LINKAGE DISEQUILIBRIUM, Male, Mutation, Population Dynamics, RWANDA, Selection, Genetic, Sequence Analysis, DNA, Species Specificity, Time Factors

Abstract:

Mountain gorillas are an endangered great ape subspecies and a prominent focus for conservation, yet we know little about their genomic diversity and evolutionary past. We sequenced whole genomes from multiple wild individuals and compared the genomes of all four Gorilla subspecies. We found that the two eastern subspecies have experienced a prolonged population decline over the past 100,000 years, resulting in very low genetic diversity and an increased overall burden of deleterious variation. A further recent decline in the mountain gorilla population has led to extensive inbreeding, such that individuals are typically homozygous at 34% of their sequence, leading to the purging of severely deleterious recessive mutations from the population. We discuss the causes of their decline and the consequences for their future survival.