Beta-casein A1/A2, kappa-casein and beta-lactoglobulin polymorphisms in Turkish cattle breeds

Abstract. In this study, the genetic diversity of three milk protein genes namely beta-casein, kappacasein and beta-lactoglobulin was estimated in Turkish cattle breeds. Based on these genes, breeds in Turkey have been grouped as: 1) Eastern Anatolian Red, Anatolian Black and Southern Anatolian Red and 2) Turkish Grey, Turkish Holstein and Holstein Candidate Bulls. B alleles of the three studied genes, which were reported to be positively related with cheese yield and quality, seemed to be low-intermediate for beta-casein and kappa-casein but relatively high for beta-lactoglobulin in the first group of Turkish breeds compared to other breeds of the world. The kappa-casein E allele, which has a negative effect on cheese quality, is absent in Turkish cattle breeds, except in Holstein Candidate Bulls. Therefore, the results suggest that milk of Turkish native breeds is suitable for cheese making. Based on observations of the Turkish breeds, some suggestions were made regarding breeding practices in Turkey.