Identification of Polymorphisms of the CSN2 Gene Encoding β-Casein in Greek Local Breeds of Cattle

This e research focused on the detection and identification of genetic polymorphisms in exon 7 of the β-casein CSN2 gene in blood samples from Greek Holstein cows and from local breeds of cattle, such as Vrachykeratiki, Katerinis, and Sykias. For this purpose, DNA was isolated from 780 blood samples obtained from Greek Holstein cows, 86 from three local breeds of cattle, namely Brachyceros, Katerinis, and Sykias, and 14 from Greek buffalo. The desired region of exon 7 was amplified by PCR, resulting in 121 and 251 bp products in bovine and buffalo samples. The PCR product was digested with restriction fragment length polymorphism (RFLP) on agarose gels. The restriction enzymes DdeI and TaqI were used. All of the blood samples had the amplified size. The results showed that 74.4% of the Greek Holstein cows had the A2A2 β-casein genotype, the three native breads Vrachykeratiki had 57.7%, and the other two had 100% of the A2A2 β-casein. From the 14 Greek buffalo, 100% had the A2A2 β-casein.