Genomic footprints of recovery in the European bison

After extinction in the wild in the beginning of the twentieth century, the European bison has been successfully recovered in two distinct genetic lines from only twelve and seven captive founders. We here aimed at characterizing the levels of realized inbreeding in these two restored lines to provide empirical insights into the genomic footprints left by population recovery from a small number of founders. To that end, we genotyped 183 European bison born over the last 40 years with the Illumina BovineHD beadchip that contained 22,602 informative autosomal SNPs after data filtering. We then identified homozygous-by-descent (HBD) segments and classified them into different age-related classes relying on a model-based approach. As expected, we observed that the strong and recent founder effect experienced by the two lines resulted in very high levels of recent inbreeding and in the presence of long HBD tracks (up to 120 Mb). These long HBD tracks were associated with ancestors living app...