Identification of K-Casein Polymorphism in Bali Cattle

The present study was conducted to identify K-casein （Kappa-casein） polymorphism in the Bali cattle （Bos sondaicus）. A 780 bp specific fragment of K-casein gene spanning from the forth exon region （517 bp） to forth intron （263 bp） was amplified from 60 individuals from the Bali Cattle Breeding Centre in Jembrana regency, Bali province. PCR-RFLP analysis with HindlII indicated that only the BB genotype was found at locus I, while with PstI indicated that two genotypes AA and AB were found at the k-casein locus If. The frequencies of A and B alleles at locus II were 0.91 and 0.09, respectively. Mutations in locus II did not change the amino acid coding （silent mutation）. At locus I, comparison with allele frequencies in other cattle breeds indicates that frequencies in Bali cattle （Bos sondaicus） are significantly different from those observed in Bos taurus and Bos indicus breeds.