Kappa casein gene polymorphism in local Tunisian goats.

The genetic polymorphism of the goat Kappa casein was investigated in Tunisian goats. Blood samples were collected from local goat breeds. Samples of genomic DNA were obtained from leukocytes of 175 dairy goats and regions of interest in the gene were amplified by Polymerase Chain Reaction (PCR) and then evaluated in agarose gel. For a better characterization of the single nucleotide polymorphism, a PCR-Restriction Fragment Length Polymorphism was performed employing the endonuclease DNA amplification using 459 bp primers. The PCR products of primers (459 bp) digested by restriction enzyme Alw44I produced two fragments of 459 and 381 bp. The Kappa casein allelic variants in tested animals revealed different genotypes, two of them were homozygous: AA or BB, AC or BC and CC. Genotypic frequencies were 12.5, 60.5 and 27% for AA or BB, CC and AC or BC, respectively. Identification of different variants of the Kappa casein can be used for the improvement and conservation of Tunisian local goats.