Determination of a possible relationship between a single nucleotide polymorphism (SNP) in the promoter region of the gene and production and reproduction traits in the Agerolese cattle breed.

Sirtuins (sir2-like proteins) belong to the family of class III NAD -dependent histone deacetylases. Among them, SIRT1 is the most studied sirtuin. It plays a key role in many biological processes in the liver, adipose tissue, muscle, pancreas, testis, ovary and mammary gland. It has an important function in endocrine signaling, with a specific role in glucose and fat metabolism. To date, in bovine species, only few SIRT1 single nucleotide polymorphisms (SNPs) have been reported in the literature. Thus, the aims of the present study were to estimate the allele and genotype frequencies at the g.-274C   G locus in the promoter region of the SIRT1 gene and to investigate, for the first time, the relationship among different genotypes and milk production and some reproduction traits in a sample of cows belonging to the Agerolese breed. All the animals were genotyped at the abovementioned locus using the PCR-RFLP technique. The investigated population was found to be polymorphic at the investigated locus. Concerning milk production performances, significant differences between genotypes were found in daily milk yield (DMY), fat percentage (FC), lactation length (LL), peak daily milk yield (PY) and 305-day milk yield (305MY). Moreover, the effect of the g.-274C   G genotype on age at first calving and calving period was significant. In conclusion, our findings are promising and should encourage scientists to further investigate the effect of genetic polymorphism of sirtuins on milk performance and reproductive traits.