Assessment of polymorphism on kappa-casein gene of Anatolian water buffalo breed using the PCR-RFLP method

Water buffalo breeding is practiced in various provinces of Turkey, and is also included in the National Breeding Project. It was aimed in this study to investigate polymorphisms on exon 4-intron 5 and exon 4 only of the kappa-casein (CSN3) gene for milk yields of water buffalo bred in Sivas Province. Blood samples were taken from 135 water buffaloes. The phenol/chloroform method for DNA extraction was conducted on collected blood. Polymerase chain reaction (PCR) was used to amplify CSN3-specific regions, and amplified products were run using 2% agarose gel electrophoresis (AGE). Various restriction endonucleases (RE) were utilized in respect to their protocols to investigate polymorphisms in amplified products. Following the RE digestion, mixtures were run in 2.5% AGE. It was observed that only the BB genotype was obtained in terms of Hinf I enzyme; however, the E allele (Mae III) was not obtained for the CSN3 gene. For the Hind III enzyme, only the BB genotype was obtained from exon 4 of the CSN3 gene, while both AB (27.41%) and BB (72.59%) genotypes were determined from exon 4-intron 5 of the CSN3 gene. No statistical difference was detected for genotypes of the restriction enzymes used in Anatolian water buffaloes (P > 0.05). In conclusion, the Hinf I/BB genotype, associated with higher milk protein amount and milk fat, was observed in Anatolian water buffaloes.