Identification of four novel alleles of the BoLA-DRB3 upstream regulatory region in Chinese yellow cattle.

The sequence of upstream regulatory region (URR) of BoLA-DRB3 gene was amplified with polymerase chain reaction followed by DNA sequencing from six animals of Chinese yellow cattle. A total of five alleles including four newly identified ones, named BoLA-DRB3*R-03-U2, BoLA-DRB3*R-06-U2, BoLA-DRB3*R-07-U and BoLA-DRB3*R-12-U for the BoLA-DRB3 URR were found. Result of sequence analysis showed that the regulatory elements W, X, Y, CCAAT and TATA-like boxes existed in such URRs and 16 polymorphic sites (11 transitions, 3 transversions, 1 deletion and 1 insertion) located in the spacers between the conserved consensus boxes and 1 insertion within X box, while no new polymorphic site within the consensus boxes.