Genomic analyses for adaptation of Italian cattle breeds: preliminary results. The BOVITA Project

Climate change will impact diverse geographic areas, including the Mediterranean region. Understanding the adaptive ability of livestock to climate variations has become a crucial focus in biodiversity conservation and management. Cattle breeds are valuable genetic resources to understand and study the molecular mechanisms of adaptation to their specific environments. Several landscape genomics approaches have been proposed to detect adaptation to different environmental pressures including correlative genotype-environment associations. The BOVITA project aims at characterizing the genetic basis of adaptation for 755 individuals from 30 Italian local cattle breeds. Here we present the first results of a joint analysis of genetic and climatic data. By considering Bovine 50K SNP genotyping data and four climate variables data from Climond database (i.e. annual temperature, annual precipitation, annual mean radiation, and annual mean moisture index). To identify genomic regions harboring footprints of selection, a whole-genome scan for adaptive differentiation was performed using genotyping data with the XtX model implemented in the BAYPASS software. In addition, whole-genome scans for association with the population-specific climatic variables were performed using the AUX model. Footprints of selection were detected on BTA1, BTA4, BTA5, BTA6, BTA7, BTA12, BTA13, BTA14, BTA16, BTA20 pointing out several candidate genes (e.g. ST3GAL6, NUDCD3, CCND2, ABCG2, LCORL, VDAC1, MIR466B-2, CTNNBL1, XKR4, CDC42BPA, SLC45A2, RXFP3); moreover, different genomic regions (on BTA7, BTA19, and BTA20) were associated with the annual mean moisture index. Ongoing analyses will specify candidate regions and genes involved in local adaptation.