Genomic evidence for inbreeding depression and purging of deleterious genetic variation in Indian tigers

Habitat fragmentation is sequestering species into small and isolated populations, with high chances of extinction. Are small and isolated populations at risk for extinction from inbreeding depression? Or does inbreeding and purging of deleterious alleles reduce such threat? Using whole genomes from several wild Indian tiger populations, we provide evidence supporting purging of highly deleterious variants in a small-isolated population. However, our analyses also indicate that the remaining highly deleterious alleles are at high frequencies, suggesting continued inbreeding depression despite some successful purging. We discuss the implications of our results for conservation, including possible genomics-informed genetic rescue strategies.