DGAT1p.K232A polymorphism in dairy and dual purpose Italian cattle breeds

Abstract

The aim of this study was to evaluate the allele frequency distribution at the DGAT1 p.K232A polymorphic site in seven Italian dairy and dual purpose cattle breeds. On the whole, 651 animals belonging Italian Holstein (116), Italian Brown (105), Italian Simmental (95), Valdostana Red Pied (95), Rendena (62), Reggiana (128) and Modenese (50) were genotyped by PCR-RFLP. Sequencing was carried out to confirm results of the genotyping protocol. The DGAT1 p.232K allele was identified in Italian Holstein (25.4%), Reggiana (17.2%), and with very low frequency in Italian Simmental, Valdostana Red Pied and Rendena (1%). In Italian Brown and Modenese, this allele was not detected. These results indicated that this polymorphic site can be considered for association studies only in Italian Holstein and Reggiana breeds. Deviation from Hardy-Weinberg equilibrium was observed in the Reggiana breed (P<0.01) in which there was an excess of heterozygous sires and absence of animals with the p.232KK genotype. This result should be further evaluated because the analysed sires represented almost all bulls available for artificial insemination in this breed. Comparison of allele frequencies at the DGAT1 locus with several other Holstein populations showed a wide range of variability, probably due to different selection strategies adopted

The effect of sex and DGAT1 gene polymorphism on fat deposition traits in simmental beef cattle

“…Besides, the activity of delta-9-desaturase, which converts SFA into MUFA, increases significantly with an increase in adipose tissue mass (Smith et al, 2006), leading to a general increase in fat unsaturation. However, in these studies on Holstain and Angus populations the significant effect on IMF content was observed for DGAT1 KK genotype which was not found in the Simmental population examined in the present study or elsewhere (Scotti et al, 2010;Pannier et al, 2010). In the present study there was no effect of DGAT1 locus on IMF content or FA composition.…”

“…Previous studies on Simmental cattle from several countries have shown the absence (or almost complete absence) of variability at the DGAT1 locus, with a generally very low frequency of lysine allele (Kaupe et al, 2004;Pannier et al, 2010;Scotti et al, 2010). The aim of the present study was to estimate the allele and genotype frequencies of single nucleotide polymorphisms of the DGAT1 gene and to associate genotypes with carcass and muscle fat deposition traits in the Croatian population of Simmental cattle.…”

Association of 20 candidate gene markers with milk production and composition traits in sires of Reggiana breed, a local dairy cattle population

“…This actually is an important objective for the selection of the Reggiana breed whose milk is devoted exclusively to the production of Parmigiano-Reggiano cheese. Moreover, it is also interesting to note that the Reggiana breed is the only Italian dairy cattle breed together with the Italian Holstein that has a relatively high frequency of the K allele (Scotti et al, 2010).…”

Searching new signals for production traits through gene-based association analysis in three Italian cattle breeds

“…This is probably due to the low frequency of the p.[232Lys] allele in Italian Simmental (Scotti et al . ) and to the different selection strategies used between these breeds.…”