Molecular evolution of human immunodeficiency virus type 1 subtype A in Senegal: 1988-1997.
OBJECTIVE
Few studies have been able to track the genetic diversity of HIV-1 viruses in human populations over time. We analyzed the molecular evolution of subtype A over a 10-year period, in a cohort of female sex workers with a known time of infection.


METHODS
We amplified and sequenced the C2-V3 region of the surface envelope glycoprotein from 73 HIV-1-infected women, infected between 1987-1997.


RESULTS
Fifty-one patients were infected by subtype A viruses. The viruses demonstrated significant diversification (p < 0.001) with mean genetic distance increasing from 8.6% in 1989 to 15.9% in 1997. The slope of the fitted curve suggested a rate of diversification of 0.7% per year. The majority of subtype A viruses clustered with HIV-1 subtype A/G recombinant form (IbNG).


CONCLUSIONS
The genetic diversity of HIV-1 subtype A infections doubled over the first 10 years of this high risk population's epidemic, suggesting that implementation of vaccines early in the epidemic may have a higher likelihood of success based on levels of genetic diversity. The A/G recombinant form (IbNG) has taken epidemic proportions in West Africa. This is of particular importance in understanding the epidemiology of HIV-1 subtypes in Africa and to further dissect the potential phenotypic and biological characteristics of these viruses.
Sankalé
J L
JL
Department of Immunology, and Infectious Diseases, Harvard School of Public Health and Harvard AIDS Institute, Boston, Massachusetts 02115, USA.
Hamel
D
D
Woolsey
A
A
Traoré
T
T
Dia
T C
TC
Guèye-Ndiaye
A
A
Essex
M
M
Mboup
T
T
Kanki
P
P
D015331:Cohort Studies; D004279:DNA, Viral / Q000032:analysis; D019143:Evolution, Molecular; D005260:Female; D015683:Gene Products, gag / Q000235:genetics; D014644:Genetic Variation; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D006801:Humans; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D012675:Senegal / Q000453:epidemiology; D011477:Sex Work; D014759:Viral Envelope Proteins / Q000235:genetics
D004279:DNA, Viral; D015683:Gene Products, gag; D012367:RNA, Viral; D014759:Viral Envelope Proteins