Short communication: Predominance of β-casein (CSN2) C allele in goat breeds reared in Italy

A protocol for the rapid and simultaneous genotyping of A, C, and 0′ CSN2 alleles in goat was developed by single strand conformational polymorphism polymer- ase chain reaction (SSCP-PCR) technique. Screening the CSN2 variability in 7 goat breeds reared in Italy validated the genotyping test. The SSCP-PCR tech- nique was also suitable for monitoring CSN2 polymor- phism. In particular, the discrimination between CSN2*A and CSN2*C is important because the 2 cor- responding protein variants cannot be separated by standard typing techniques. The monitoring of CSN2 variability in the goat breeds indicates the predomi- nance of the C allele. In most breeds, CSN2*C occurred with the highest frequency, except in Saanen where CSN2*A and CSN2*C showed similar frequencies. Variant CSN2*C occurred with a frequency of 0.68 (Ca- mosciata), 0.70 (Jonica), 0.71 (Garganica), 0.82 (Mal- tese), 0.87 (Cilentana), and 0.97 (Orobica). The align- ment among the mature CSN2 sequences of different species suggests that CSN2*A is the ancestral allele compared with CSN2*C. Interestingly, the CSN2*A goat variant showed higher frequencies in selected breeds (Saanen and Camosciata).