Polymorphism Of Three Milk Protein Genes in Mexican Jersey Cattle

Abstract Text: The main task was to estimate the allelic and genotypic frequencies, genetic diversity and polymorphic information content for the β-casein, κ-casein and β-lactoglobulin genes. Blood and frozen semen samples were collected of 453 Jersey individuals registered by the Mexican Jersey Cattle Association. 28 breed specific SNP primers for whole genes were used. The B allele of κ-casein had higher frequency (0.80) than the A (0.15) and E (0.05). For β-lactoglobulin, the highest frequency was for B (0.76), followed by A and C alleles (0.22 and 0.02, respectively). The β-casein allele with higher frequency was A² (0.62), followed by A¹ (0.18), A³ (0.09) and B (0.11). The average genetic diversity (H_e) was 0.424, with a locus effective allele number of 0.5. These results indicated a high allelic diversity of κ-caseín, β-casein and β-lactoglobulin in Mexican Jersey cattle. 

Keywords: k-casein, β-casein, β-lactoglobulin, genetic polymorphism