Exploring polymorphisms and effects of candidate genes on milk fat quality in dairy sheep (original) (raw)

FASN, SCD1 and ANXA9 gene polymorphism as genetic predictors of the fatty acid profile of sheep milk

Scientific Reports, 2021

In this study, single nucleotide polymorphisms (SNPs) in the ANXA9 (annexin 9), FASN (fatty acid synthase) and SCD1 (stearoyl-CoA desaturase 1) genes were analyzed as factors influencing fatty acid profiles in milk from Zošľachtená valaška sheep. SNP in selected genes was identified using polymerase chain reaction (PCR) and restriction fragment length polymorphism (PCR–RFLP). The long-chain fatty acids profile in sheep milk was identified by gas chromatography. Statistical analysis of the SCD1/Cfr13I polymorphism showed that the milk of the homozygous AA animals was characterized by a lower (P < 0.05) share of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0 in comparison to the homozygous CC sheep. The milk of heterozygous sheep was characterized by a higher (P < 0.05) proportion of C13:0 acid compared to the milk of sheep with the homozygous AA type. A higher (P < 0.05) level of saturated fatty acids (SFA) was found in the milk of CC genotype sheep compared to the AA genotype. Our r...

Genetic variation of C18:1 and C18:2 isomers in sheep milk fat

Small Ruminant Research

The aim of the present study was to evaluate the genetic variation of milk fat CLA, together with the variation of CLA precursors, including the individual PUFA that are potentially involved in the metabolic pathway of CLA. The allelic substitution effect, upon these FA, was estimated for a number of polymorphisms, that are located within 9 candidate genes known to influence milk FA partitioning. Sheep milk was chosen because it contains higher total fat percentage, and higher CLA levels per gram fat, than milk of other ruminants. Milk FAME analyses were performed on individual milk samples of sheep from three different breeds. Our results reflect the association of three genes (alpha-1-antichymotrypsin; diacylglycerol O-acyltransferase homolog-2; and zona pellucida glycoprotein-2) with the values of both linolenic FA and CLA; of three more genes (insulin-like growth factor I; lecithin-cholesterol acyltransferase and propionyl coenzyme A carboxylase, beta polypeptide) with the variability of linolenic FA; and of one gene, the fatty acid synthetase with the variability of CLA and stearic FA. The current study might contribute to the understanding of the metabolic pathway of PUFA in sheep milk, providing suggestions to modify milk fat composition through selection.

Milk fatty acid variability: effect of some candidate genes involved in lipid synthesis

Journal of Dairy Research, 2013

In this work, the genetic variation of milk FA was investigated in three different bovine breeds, the Jersey, the Piedmontese and the Valdostana, and at different lactation stages. All animals were genotyped for 21 Single Nucleotide Polymorphisms located within nine candidate genes involved in lipid synthesis: diacylglycerol acyltransferase 1 and 2 (DGAT1, 2); stearoyl-CoA desaturase (SCD); growth hormone receptor (GHR); fatty acid synthase (FASN); acyl-CoA dehydrogenase (ACAD); fatty acid binding protein (FABP4); lipoprotein lipase (LPL); and leptin gene (LEP). The highest milk-fat Jersey breed also showed the highest content of saturated FA. Throughout lactation, the breeds showed a similar variation in the FA, with a decrease in the short-chain, this was accompanied by a general increase in the long chain FA at the end of lactation. The increase in long chain saturated FA was particularly evident in the case of the Jersey. The effect of SCD gene on the C14 desaturation index was ...

Identification of genetic polymorphisms in the stearoyl CoA desaturase gene and its association with milk quality traits in Najdi sheep

Open Chemistry

The nutritional quality of milk, which is determined by its fatty acid (FA) composition, and the candidate gene stearoyl-CoA desaturase (SCD) can be used in conjunction with these traits to improve the quality of dairy products. The aim of this study was to identify single nucleotide polymorphism (SNP) of the SCD gene and its associations with the milk composition and FA profiles of Najdi dairy sheep and 72 multiparous Najdi ewes under the same feeding system. Milk and blood samples were taken during the first lactation (<30 days in milk). Analysis and alignment DNA sequences identified SNP g.87C>A in the promoter and SNP g.1033G>A in exon 2 of the SCD gene. Association analysis showed that SNP g.87C>A was significantly associated (P ≤ 0.05) with palmitic acid (C16:0), alpha linoleic acid (ALA – C18:3-n3), linolenic acid (LA – C18:2-n6), and polyunsaturated fatty acid (PUFA). In addition, the SNP g.1033G>A showed a significant (P < 0.05) association with odd-chain ...

Association of single nucleotide polymorphisms in the fatty acid synthase, LOC514211, and fat mass and obesity-associated genes with milk traits in Indonesian-Holstein dairy cattle

Veterinary World, 2019

Association of single nucleotide polymorphisms in the fatty acid synthase, LOC514211, and fat mass and obesity-associated genes with milk traits in Indonesian-Holstein dairy cattle, Veterinary World, 12(7): 1160-1166. Abstract Aim: The study aimed to identify fatty acid synthase (FASN), LOC514211, and fat mass and obesity-associated (FTO) gene polymorphisms and to investigate their associations with milk traits in an Indonesian-Holstein dairy cow population. Materials and Methods: A total of 100 Indonesian-Holstein cows consisting of 50 heads (0 th generation; G 0) and 50 heads of their daughters (1 st generation; G 1) were used. Polymerase chain reaction-restriction fragment length polymorphism was performed to genotype three single nucleotide polymorphisms: rs41919985 in the FASN gene, rs42688595 in the LOC514211 gene, and g.1371T>A in the FTO gene. Results: FASN rs41919985 was associated with milk protein percentage (p<0.05), FTO g.1371T>A was associated with milk fat percentage (p<0.05), and LOC514211 rs42688595 was not associated with any trait (p>0.05). Heterozygote variants showed a higher protein percentage for FASN and the highest fat percentage for FTO. These associations were consistent in the G 0 and G 1 populations. Conclusion: Our results indicate that the milk protein and fat percentages can be improved by increasing the frequency of the AG genotype of FASN and the AT genotype of FTO, respectively.

Effects of Single Nucleotide Polymorphisms in the SLC27A3 Gene on the Nutritional Value of Sheep Milk

Animals

The current research was undertaken to use the genetic potential of animals to obtain high-quality dairy products. Single nucleotide polymorphisms (SNPs) in SLC27A3 gene were identified in Zošľachtená valaška sheep using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Correlations between genotypes and milk composition and nutritional value were analysed This study showed that milk from sheep with TT genotype in the SNP4 locus was characterised by higher (p < 0.01) fat and dry matter content and lower lactose concentration, compared to sheep with AA and TA genotypes, respectively. Moreover, it was found that animals with GG genotype in SNP1 produced milk with higher C18:1n9c, C18:1n7t, CLA, and other unsaturated fatty acids (UFAs) content than sheep with TT. Additionally, milk from animals with CC at the SNP3 locus had significantly higher (p < 0.01) levels of UFAs than milk from sheep with other genotypes in the SNP3. In summary, it may be concl...