Cattle

Alleles A1 and A2 of the Bos taurus CSN2 gene are the most common in a number of dairy cattle breeds. A genetic variant of the bovine β-casein gene includes A1 and B which encodes a histidine residue at codon 67, resulting in potential liberation of a bioactive peptide, β-casomorphin, upon digestion. This is an opium family substance, and has been associated with a large number of clinical implications in humans. Study includes amplification of bovine β-casein gene and further differentiation of variants A1 and A2 beta casein in cows. Conventional PCR was done to amplify β-casein gene in three hundred and one specimens. Further eighty amplicons were sent for sequencing. From the sequenced data, 24 were A2 homozygous (A2A2), 11were A1 homozygous (A1A1) and 37 heterozygous (A1A2). Allele discrimination in cows will be significant for the farmers, breeding programmes as well as for dairy industries as the milk variant determination will predict the outcome of the beta casein variants which are of utmost clinical relevance.