Discovery of natural variant strain of HIV1 in env gene C2-V3 encoded PND of membrane protein

OBJECTIVE: To sequence and analyze the env gene C2-V3 region of proviral genome from a HIV1 isolate(WWBH7) which was obtained from Huadong Area in China. METHODS: The env gene C2-V3 DNA fragment was amplified by nested-primer PCR with genome DNA of eripheral blood mononuclear cells from a confirmed HIV1 infected individual as a template. The amplified DNA fragment was inserted into pGEM-T vector. The recombinant plasmid was confirmed by restriction enzyme analysis. The inserted DNA fragment was sequenced by ABI737 autosequencer and analyzed by PROSIS software. RESULTS: The HIV1 strain was the derivatives of HIV1 B subtype. But there was mutation of 192 bp fragment repeated insertion at env C2-V3 region of the HIV1 strain compared with standard HIV1 B subtype such as SF2 strain. The mutation brought about a double V3 region in gene encoded PND (principal neutralizing domains). The DNA sequence was registered in GenBank (AF220245). CONCLUSIONS: This was a natural mutated variant strain of HIV1 whose genome showed a 192 bp repeated insertion at C2-V3 region of env gene encoded PND of membrane protein.