Genetic rescue of Florida Panthers reduced homozygosity but did not swamp ancestral genotypes

We demonstrate the impact of genetic rescue on the Florida panther (P. concolor) population by integrating whole-genome sequencing data with genetic simulations.

Our results indicate that genetic rescue effectively reduced the inbreeding level of the population and enhanced its genetic diversity - specifically by decreasing homozygosity of deleterious variants, increasing genetic variation, lowering relatedness, and reducing runs of homozygosity (ROHs). We inferred the local ancestry of the admixed pumas and found that no genomic regions were completely replaced by the Texas lineage, thereby ruling out the possibility of genetic swamping. Furthermore, we discovered that the beneficial effects of genetic rescue stem from increased heterozygosity - which mitigates the impact of deleterious recessive alleles rather than from a reduction in the total number of deleterious alleles.