Haplotype distribution in the class I sirtuin genes and their associations with ultrasound carcass traits in Qinchuan cattle (Bos taurus)

• We identified seven novel single nucleotide polymorphisms (SNPs) within bovine class I sirtuin genes.
• We analyzed the genotype distribution and genetic diversity seven SNPs within bovine class I sirtuin genes.
• Haplotype analyses of the seven SNPs were conducted.
• Association of the polymorphism locus and ultrasound carcass traits were found in Qinchuan cattle.

Class I sirtuin genes including SIRT1, SIRT2 and SIRT3, are members of the nicotinamide adenine dinucleotide (NAD)-dependent family of histone deacetylases, and play essential roles in senescence, metabolism, and apoptosis. This study was conducted to detect potential polymorphisms of the bovine class I sirtuin genes and explore their relationships with ultrasound carcass traits in Qinchuan cattle. Four non-coding mutations in the 3′UTR (SIRT1: g.25751A > C, SIRT1: g.25846A > G, SIRT2: g.19676G > A and SIRT3: g. 25702C > T) and three mutations in exons (SIRT2: g.4062C > T; SIRT2: g.4406C > T and SIRT3: g.25557A > G) were identified in 468 individuals of Qinchuan cattle. Chi-square tests showed that g.25751A > C, g.19676G > A, and g.25702C > T were in Hardy-Weinberg disequilibrium (χ2 < χ0.052). The statistical analyses indicated that six SNPs were significantly associated with the ultrasound carcass traits (P < 0.05) except g.4062C > T (SIRT2) (P > 0.05). These results indicate that the variations in the class I sirtuin genes and their corresponding genotypes may be considered as molecular markers for economic traits in cattle breeding.