Complete nef gene sequence of HIV type 1 subtype B' from professional plasma donors in the People's Republic of China.

Abstract

Probably more than 150,000 people are infected with HIV in China. Although HIV-1 infection was initially limited to the southern province of Yunnan, it is increasingly spreading in the interior of the country, and multiple HIV-1 subtypes have been identified, including B, C, and E. Envelope (env) gene sequences of HIV-1 strains from Yunnan resemble HIV subtype B' strains from Thailand. The authors analyzed the nef gene from HIV-1-infected professional plasma donors to determine if deletions and/or insertions are present in the nef gene of HIV-1 strains from China. Blood was collected from 3 men of mean age 42 years and 4 women of mean age 40 between December 1996 and April 1997 in eastern China, blotted onto neonatal 903 filter paper and allowed to dry, then analyzed. Sequence alignment and comparison of the gene found that the HIV-1 strains from China diverged from well-characterized subtype B strains from North America, Thailand, and Papua New Guinea by 9.6-16.7% and 8-20% at the nucleotide and deduced amino acid levels, respectively. On the basis of sequence and phylogenetic analyses of a 550-nucleotide region spanning the main neutralizing domain, the V3 loop, of the gp120-encoding env gene, all of the 7 strains from China were more similar to the subtype B' HIV of Thailand than to the subtype B of North America.