Sequencing and phylogenetic analysis of Bovine Leukosis Virus Tax gene in Iran

Bovine Leukosis Virus (BLV) belongs to the genus Deltaretrovirus ,subfamily Orthoretrovirinae of the family Retroviridae comprising 3 main genes of gag, pol and env and a number of replication regulatory genes such as Tax, Rex, R III, C IV. For determination of genetic relationship of Tax gene of BLV in Iran with those in other countries fragments 927bp corresponding to Tax from four infected samples were amplified in PCR system and sequenced for determining nucleotide sequence and compared with identified nucleotide sequence of this gene in other countries.A comparison made on Tax gene in Iran with other countries demonstrated 3.4 to 7.7% variability in Tax gene, of which the greatest sequence similarity exists between sequences of Tax in Iran with USA (AY700378.1)with 96.6% similarity and the least relationship exists between sequences of this virus in Iran with Australia (AY700379.1) and Japan (AY700381.1) with 92.3% similarity