Genetic diversity of human immunodeficiency virus-1 isolates in Paraná, Brazil

Because epidemiological data on circulating HIV subtypes among HIV-positive patients in the state of Paraná were not known until now, the aims of this study were to describe the genetic diversity profile of HIV-1 in treated patients in Paraná, Brazil, and report the differences in protease (PR) and reverse transcriptase (RT) mutations in HIV-1 subtypes.

A cross-sectional study was conducted from 2003 to 2006. Plasma viral RNA of 389 patients was extracted and PR and RT genes were polymerase chain reaction-amplified and sequenced. Sequences were subtyped and examined for antiretroviral resistance mutations. Data on gender of patient harboring the viruses and past history of antiretroviral treatment were also collected.

Most viruses were either subtype B (61.44%) or subtype C (20.57%). Subtype C and F were more frequent in women (p < 0.00). The prevalence of subtypes was similar over the years studied. The most frequent RT mutations in all subtypes were M184V and mutations at codons 215, 41, 103, 67, 219, and 190. Mutations 41L, 210W, 215YF, and 74V were significantly more prevalent on subtype B, and the mutation 106M was significantly more prevalent on subtype C. The most frequent major PI mutations in all subtypes occurred at codons 46, 82, and 90. PR mutations 32I, 46I, and 84V were significantly more prevalent on subtype B. The minor PI mutations on codons 36, 93, and 63 were more prevalent on subtypes F, C, and B, respectively.

We concluded that the predominant strain of HIV-1 in Paraná is subtype B, followed by subtype C. Some mutations at PR and TR had subtype predominance in accordance with other authors' report.