Influence of single nucleotide polymorphisms in some candidate genes related to the performance traits in Italian beef cattle breeds

Because Italy has a long history in beef cattle production, Italian beef cattle breeds such as Chianina, Marchigiana, and Romagnola have always been connected with rural and ethnic traditions, and they became very popular as a result of consumers response to the Bovine Spongiform Encephalopathy (BSE) outbreak and animal welfare in the last years. These three breeds are selected by ANABIC (the National Association of Italian Beef Cattle Breeders), and their selection is focused on choosing young bulls after the performance test. In this study, 15 Single Nucleotide Polymorphisms (SNPs) in 10 candidate genes (growth hormone receptor, growth differentiation factor 8, ghrelin, leptin, myogenic factor 5, insulin-like growth factor 2, leptin receptor, uncoupling protein 2, uncoupling protein 3, and melanocortin 4 receptor) possibly related to the performance traits were analysed by assessing their effects on weights in the three above-mentioned breeds. During their performance test, the weights of 1196 young bulls were registered and were subsequently used to search for an association with the 15 SNPs; in addition to the registered data, the Best Linear Unbiased Prediction Animal Model (BLUP-AM) indexes computed by ANABIC were considered. Although the genotypic frequencies of several SNPs are rather similar in the breeds, the main differences were found between Romagnola and Chianina. For the first time, the present study highlights the potential application of some SNPs polymorphisms in the selection procedures of the Italian Beef Cattle breeds. The most important SNPs seem to be LEP_1, MYF5, GHR_1 and MC4R; in fact, a general view of the SNPs average allele substitution effect on weights shows the influence of LEP_1 in both Chianina and Marchigiana, MC4R in both Marchigiana and Romagnola, MYF5 and GHR_1 in Marchigiana. The information of these markers could be taken into account in the breeding scheme of the Italian beef cattle breeds to increase the genetic gain for some of their breeding goals.