ALLELIC AND GENOTYPIC FREQUENCY OF THE KAPPA CASEIN GENE IN DOUBLE PURPOSE CATTLE

Abstract

In this work, allelic frequencies (A and B) of CASï« gene were determined as selection criteria on milk quality in double purpose cattle. Blood samples were taken at 200 bovine females and were placed in tubes containing EDTA. Genetic marker MB002 was amplified from extracted genetic material. RFLP testing was performed using restriction enzyme Hinf I for the diagnosis of A and B alleles on CASκ. Genotype frequencies obtained corresponded to 0.34, 0.01 and 0.65 for AA, BB and AB, respectively. Allelic frequency were 0.67 and 0.33 for A and B alleles, respectively. Also, there was a heterocigocity average of 0.6481. The study population is not in Hardy Weinberg equilibrium, the value of ï£2 = 14.8 with 2 degrees of freedom (P < 0.005). Based on allelic frequency of CASï« B (0.34) observed in this study under theoretical assumptions, double-purpose cattle may be a feasible option to increase milk quality when BB sires are used for cross breeding. In this way, B alleles associated to higher milk quality can be enriched in few generations.