Nucleotide sequence of DR-B exon of major histocompatibility complex from an Indian zebu cattle breed.

The Indian cattle is known to be more tolerant to tropical infections than the European cattle. In order to verify the genetic basis of this variation, the DR B exon-2 of the major histocompatibility locus, known for coding the antigen recognition site, from the Hallikar breed of Indian cattle was amplified by PCR, cloned and sequenced. Comparison of this sequence with the information available on taurus cattle brought out six unique nucleotide changes and three amino acid changes. The amino acid positions were at 17, 72 and 87. A major variable region was observed at amino acid position 85 to 87 from all the alleles so far reported for the bovine locus.