Emergence and diversity of different HIV-1 subtypes in South Africa, 2000-2001.
HIV-1 is a major health problem in South Africa with an average prevalence rate of 29.1% in pregnant women and between 4.9 and 6.1 million people infected. Using env gp120 V3 serotyping and genotyping techniques 410 patient samples were investigated. Most of the samples were obtained from different clinics in the greater Cape Town area of the Western Cape Province in South Africa. These included an academic hospital, state and private clinics, an informal settlement, sex worker cohorts, and the blood transfusion services. RNA was extracted from plasma samples followed by RT-PCR and sequencing of the env gp120 V3 region. Sequence fragments were assembled using Sequencher V4.7 and subsequently codon aligned. Distance calculation, tree construction methods, and bootstrap analysis were implemented using MEGA version 4.0. Viral load measurements indicated that HIV-1 RNA levels from 74 samples were below the assay detection limit. Three hundred thirty-six samples were used for env PCR and sequencing and 320 were assigned to subtypes. The majority of the sequences were subtyped as C (n = 285, 89.0%). Other subtypes detected were subtype A (n = 10, 3.1%); subtype B (n = 22, 6.8%); one each of subtypes F1, G, U, and a CH recombinant. Whether this diversity will have major implications for HIV-1 evolution and vaccine development in this region remains undetermined.
Division of Medical Virology, National Health Laboratory Service, University of Stellenbosch, Tygerberg, Cape Town 7505, South Africa.
G B
GB
Jacobs
A G
AG
Loxton
A
A
Laten
B
B
Robson
E Janse
EJ
van Rensburg
S
S
Engelbrecht
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005260:Female; D005838:Genotype; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000276:immunology; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011110:Polymorphism, Genetic; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D012703:Serotyping; D013019:South Africa; D019562:Viral Load; D055815:Young Adult
D015699:HIV Envelope Protein gp120; C514793:gp120 protein, Human immunodeficiency virus 1