Selection of HIV variants with signature genotypic characteristics during heterosexual transmission.
BACKGROUND
Newly infected subjects acquire a limited number of human immunodeficiency virus type 1 (HIV-1) variants with specific genotypic and phenotypic features from the array of viruses present in a chronically infected transmitting partner.


METHODS
We examined HIV-1 envelope sequences from the earliest available serum sample after HIV-1 acquisition in 13 newly infected subjects and from their epidemiologically linked HIV-1-infected heterosexual partner. Samples from both members were collected on the same day in the Rakai Community Cohort Study.


RESULTS
Ten couples were infected with subtype D HIV-1, and 3 pairs had subtype A HIV-1. Newly infected subjects acquired a subset of the viruses that were circulating in the transmitting partner; transmitted variants had less diversity and divergence and were more closely related to the ancestral sequences. The majority of signature amino acid differences among donor and recipient sequences were in and immediately following the V3 loop. Envelopes from recipients were significantly shorter and had a lower V3 charge than envelopes from donors, but there was no significant difference in the number of potential N-linked glycosylation sites.


CONCLUSIONS
A minority subset of HIV-1 variants with signature genotypes is favored for transmission in this population.
Sagar
Manish
M
Brigham and Women's Hospital, Boston, Massachusetts, USA. msagar@partners.org
Laeyendecker
Oliver
O
Lee
Sandra
S
Gamiel
Jordyn
J
Wawer
Maria J
MJ
Gray
Ronald H
RH
Serwadda
David
D
Sewankambo
Nelson K
NK
Shepherd
James C
JC
Toma
Jonathan
J
Huang
Wei
W
Quinn
Thomas C
TC
D005260:Female; D014644:Genetic Variation; D005838:Genotype; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000235:genetics; D015658:HIV Infections / Q000635:transmission* / Q000821:virology*; D015497:HIV-1 / Q000235:genetics*; D020010:Heterosexuality; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D019713:Receptors, CCR5 / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D018709:Statistics, Nonparametric; D054299:env Gene Products, Human Immunodeficiency Virus / Q000737:chemistry / Q000235:genetics; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000737:chemistry / Q000235:genetics
C527276:CXCR4 protein, human; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D019713:Receptors, CCR5; D019718:Receptors, CXCR4; D054299:env Gene Products, Human Immunodeficiency Virus; D054301:gag Gene Products, Human Immunodeficiency Virus