Identification of novel single nucleotide polymorphisms in the DGAT1 gene of buffaloes by PCR-SSCP

Abstract

Diacylglycerol O-acyltransferase 1 (DGAT1) is a microsomal enzyme that catalyzes the final step of triglyceride synthesis. The DGAT1 gene is a strong functional candidate for determining milk fat content in cattle. In this work, we used PCR-SSCP (polymerase chain reaction-single-strand conformation polymorphism) and DNA sequencing to examine polymorphism in the region spanning exon 7 to exon 9 of the DGAT1 gene in Murrah and Pandharpuri buffaloes. Three alleles (A, B and C) and four novel single-nucleotide polymorphisms were identified in the buffalo DGAT1 gene. The frequencies of the alleles differed between the two buffalo breeds, with allele C being present in Murrah but not in Pandharpuri buffalo. The allele variation detected in this work may influence DGAT1 expression and function. The results described here could be useful in examining the association between the DGAT1 gene and milk traits in buffalo.

Polymorphisms in the DGAT1 gene in buffaloes (Bubalus bubalis) in the Amazon

“…The allele variant A was the most frequent in all of the breed groups, and, consequently, the genotype AA was found at a high frequency in the Murrah and mixed-breed groups. Very similar results were obtained by Raut et al (2012) when studying Murrah and Pandharpuri buffaloes. Shi et al (2012) investigated Murrah buffaloes for the presence of SNPs between introns 7 and 8 of DGAT1, and detected a polymorphic point at position 256, which was observed in our study.…”

“…Four patterns of bands were found for this gene, which were sequenced and compared with those described by Raut et al (2012) Four genotypes were observed in the Murrah breed and three were observed in the Mediterranean and mixed-breed groups (Table 1). Allele variant A was the most frequent variant in the Murrah, Mediterranean, and mixed-breed groups (0.79, 0.69, and 0.77, respectively) ( Table 1).…”

“…The sequence obtained included intron 7, exon 8, and intron 8 of DGAT1 (Yuan et al, 2007), and all of the variations were detected in introns 7 and 8, as described by Raut et al (2012). However, a novel variant was detected (D), which has a different SNP configuration according to Raut et al (2012).…”

“…However, a novel variant was detected (D), which has a different SNP configuration according to Raut et al (2012). The allele variant A was the most frequent in all of the breed groups, and, consequently, the genotype AA was found at a high frequency in the Murrah and mixed-breed groups.…”

“…DGAT1 in buffaloes is approximately 8.3 kb long, contains 17 exons, and is located on the 14th chromosome (Yuan et al, 2007). SNP-type polymorphisms were found by Raut et al (2012) at the extension of exon 7 to exon 9 in DGAT1 in buffaloes, and they concluded that it would be possible to associate them with milk yield. Another study showed that minisatellite markers in DGAT1 are associated with milk constituents in buffaloes (Cardoso et al, 2015).…”