Ovine acyl CoA:diacylglycerol acyltransferase 1– molecular characterization, polymorphisms and association with milk traits

Abstract

The objective of this work was to characterize the complete coding region of the ovine acylCoA:diacylglycerol acyltransferase 1 (DGAT1) gene of three Italian sheep breeds: Sarda, Altamurana and Gentile di Puglia. Characterization was accomplished by direct sequencing of 8676 bp of the relevant DNA, including introns and partial 5' and 3' untranslated regions (UTRs). We detected five novel SNPs; one SNP (g.5553C>T) is located in intron 2, has similar frequencies in the three breeds and showed a negative association with milk fat content. More interesting is an SNP in the 5' UTR (g.127C>A), the occurrence of which is rare in the higher milk-fat breeds (Altamurana and Gentile di Puglia); it is located in the core sequence of Sp1, a putative binding site of transcription factors. This SNP showed a significant negative association with milk fat content in the Sarda sheep. Because DGAT1 plays a fundamental role in triacylglycerol synthesis, the novel detected SNP in the 5' UTR of the DGAT1 gene might explain, at least partially, the variation of fat content in the milk of Sarda sheep.

Identification of Polymorphism in Goat and Sheep DGAT1 Gene Associated with Milk Production Traits

“…In sheeps and goats the DGAT1 K232A polymorphism has not been so extensively studied, although the essential role of DGAT1 in milk fat content genetic variation makes this marker an important factor for the variety of milk traits found in individuals (Scata et al, 2009;Xu et al, 2008). The previous work done by Scata et al (2009) on possible DGAT1 polymorphism revealed a single nucleotide polymorphism (SNP) in the 5'UTR of DGAT1 woth possible in luence on milk fat percent.…”

“…The previous work done by Scata et al (2009) on possible DGAT1 polymorphism revealed a single nucleotide polymorphism (SNP) in the 5'UTR of DGAT1 woth possible in luence on milk fat percent.…”

Identification of novel single nucleotide polymorphisms in candidate genes for mutton quality in Indian sheep

“…Additionally, four alleles have been identified in the intron 12 region in New Zealand crossbred sheep by SSCP (Byun et al 2009 (Li et al 2010) and cattle (Cho et al 2008). Some variations in these genes are associated with milk fat content in sheep (Calvo et al 2004;Scata et al 2009 Identification of SNPs associated with mutton traits may not only help in improvement of the production but also provide economic gains to the rearers. Two SNPs in the GDF8 gene known to be associated with mutton quality and carcass traits in Texel (Kijas et al 2007) and New Zealand Romney sheep (Hickford et al 2010) have also been identified in Indian sheep (Arora et al 2013).…”

“…The candidate gene approach involving genes with known expression of certain proteins provides genomic information that may be used in genetic improvement of sheep in the absence of resource flocks in the country. Some candidate genes like calpain (CAPN4), calpastatin (CAST), diacylglycerol acyltransferase 1 (DGAT1) and fatty acid binding protein 3 (FABP3) have been implicated in muscle development and fat metabolism (Goll et al 1992;Calvo et al 2004;Scata et al 2009). The CAPN4 is a cytosolic endopeptidase that requires calcium for catalytic activity, whereas CAST is a specific endogenous inhibitor that acts on calpain (Ma et al 1993).…”

“…These genes are involved in muscle development, growth (Nonneman and Koohmaraie, 1999) as well as in eating quality (tenderness) of the mutton (Byun et al 2009). The DGAT1 and FABP3 are involved in fatty acid metabolism and associated with milk fat content and marbling (Scata et al 2009;Xu et al 2009). It is imperative that knowledge be acquired of the available Indian sheep populations which are as yet untouched reservoirs of potential genes defining mutton quality.…”