Variants within the 5′-flanking regions of bovine milk protein genes: I. κ-casein-encoding gene

In order to identify DNA variants within the 5-flanking region of the bovine -casein (Cn)-encoding gene, this area of the gene from 13 cows belonging to seven breeds (Holstein Friesian, Brown Swiss, German Simmental, Jersey, Galloway, Scottish Highland and Ceylon Dwarf Zebu) was analysed. For each individual, about 1 kb of the 5-flanking region including exon I was amplified by polymerase chain reaction (PCR). The biotinylated PCR product was immobilized on magnetic beads followed by direct bidirectional sequencing using an automated DNA sequencer. Fifteen DNA variants were identified, some of which are located within potential regulatory sites and possibly involved in the expression of the -casein encoding gene.Abbreviations AP2 activator protein 2 - bp base pair(s) - GRE/RC glucocorticoid response element/reverse complement - HNF3 hepatocyte nuclear factor 3 Cn -casein - MGF mammary gland-specific nuclear factor - nt nucleotid(s), OCT1 octamer-binding site 1 - PA polyacrylamide - PCR polymerase chain reaction - PMF pregnancy-specific mammary nuclear factor - kb kilobase(s) or 1000 bp