Association of the SNPs on CSN3, PPARGC1αand OPN genes with milk production traits and efficiency of cheese in Brown Swiss breed

Milk is considered as a complete food to meet parts of human daily requirements for a long time. Proteins are one of the most important ingredients of milk and play a critical role in processing technology such as cheese factory. Several factors such as genetics influence on quantity and quality of milk as well as cheese. Several genes on BTA6 are recognized to be related to milk and cheese related traits. In the current study the genetic association of three candidate genes of the region including; Osteopontin, PPARGC1α, and Kappa casein with milk and cheese related traits, were investigated in Brown Swiss cattle. Total DNA was extracted from 100 cattle by salting out procedure. Genotypes frequencies were estimated by PCR-RFLP and using specific enzymes. Four factors of efficiency fat, protein and dry matter of cheese were measured. Association between polymorphisms and breeding values and cheese quality were analyzed by GLM procedure at 5% of significant level. The results showed that the population was in Hardy-Weinberg equilibrium, except Kappa Casein locus. Significant effect was observed only in combined genotype of PPARGC1A-T19C and kappa casein with breeding values of milk production. Because of the limited samples or missing of some haplotypes, genotypes had no effect on cheese production. The increasing of the samples to demonstrate other genetic combination and using modern techniques such as dense SNPs are strongly recommended.