Identification of Novel SNPs in The regulatory Region of The Oxidized Low-Density Lipoprotein Receptor 1 (OLR1) Gene in Dairy Buffaloes (Bubalus bubalis)

Buffaloes are animals capable of transforming foods with low nutritional attributes into products with high nutrient composition, including fats and proteins. Because of this, they are known as economically important ruminants for producing dairy products, since their milk is more profitable due to the high fat content present. The investigation of candidate genes in milk production revealed that the OLR1 gene has the potential to influence production characteristics due to the role it plays in lipid and glucose metabolism. Because of this, the research aimed to find new polymorphisms in the OLR1 gene to associate them with milk production. Eighty-five females from a property located in Bujaru/PA were used. DNA extractions were performed by the phenolic method, followed by PCR, purification, and sequencing. Four new SNPs were found in the studied population. None of the SNPs showed a significant association with average milk production, nor did they present binding sites for transcription factors. Two SNPs were transitional, and two transversion types had high wild-type nucleotide allele frequencies above 0.90, 75% under Hardy Weinberg Equilibrium (HWE) conditions. The SNPs -641 (A>T), -672 (A>T), and -681 (T>C) presented negative FIS, which suggests the possibility of being selected within the population to ensure possible increases in milk production, since, for the SNP -672 A>T, it heterozygotes exhibited higher levels of average milk production compared to the homozygotes. Thus, the presence of new alleles through the observed point mutations may contribute positively to the increase in production observed in animals that have these genotypes. The present study was the first to associate SNPs with zootechnical indices of milk production in buffaloes in the OLR1 gene. However, studies focusing on the relationship between the SNPs present in the gene as well as other adjacent ones involved in milk production must be carried out in the species to validate the existing association.