Data from: Adaptive admixture in the West African bovine hybrid zone: insight from the Borgou population

Understanding the adaptive response to environmental fluctuations represents a central issue in evolutionary biology. At the population level, admixture between divergent ancestries has often been considered as an efficient short-term adaptation strategy. Cattle populations from the West African Bos taurus x Bos indicus hybrid zone represent a valuable resource to characterize the effect of such adaptive admixture at the genome level. We here provide a detailed assessment of the global and local genome ancestries of the Borgou breed, one of the most representative cattle of this hybrid zone. We analyzed a large data set consisting of 38,100 SNPs genotyped on 203 Borgou and 591 individuals representative of all the different cattle ancestries. At the global genomic level, we demonstrated the previously assumed stabilized admixed status of the Borgou breed and dated its admixture origin to approximately 21.7 (+/-1.4) generations ago, simultaneously with the great African rinderpest pandemic of the late 1880s. To characterize admixture at the local genomic level, we combined the identification of selection footprints within the Borgou genome and the functional annotation of the underlying candidate genes using systems biology tools. Overall our results suggest that the long-term presence of pathogens, the intermediate climatic and environmental conditions and the artificial selection on coat color are the main selective pressures in action in the bovine West African hybrid zone. Our analytical framework could easily be extended to other model or non-model species to understand the process that shapes the patterns of genome variability in hybrid zones.