Genetic and phylogenetic analyses of HIV-1 corroborate the transmission link hypothesis.
BACKGROUND
Phylogenetic and genetic analyses have proven a valuable tool to infer epidemiological links between human immunodeficiency virus type-1 (HIV-1) isolates. These methods were applied in the present report for studying the genetic relatedness of the viral strains involved in two episodes of suspected HIV-1 transmission.


OBJECTIVE
Provide any evidence that may help establish or refute the transmission link.


METHODS
In the first case, a leukemic patient became HIV-1 positive following the transfusion of platelets from a donor who was subsequently found to have tested false HIV-seronegative and to be sexual partner to an infected woman. In the second, a wife claimed to have acquired the infection from her husband who had concealed his infected status.


CONCLUSIONS
The viral pairs detected in each of the suspected transmission cases exhibited common amino acid signatures and low genetic distances and segregated together in phylogenetic trees, thus showing a level of genetic relatedness similar to reference pairs known with certainty to be epidemiologically linked. These findings corroborated the existence of a direct transmission link in both the episodes with a high level of confidence.
Pistello
Mauro
M
Retrovirus Center and Virology Section, Department of Experimental Pathology, University of Pisa, Via San Zeno 35, I-56127 Pisa, Italy. pistello@biomed.unipi.it
Del Santo
Barbara
B
Buttò
Stefano
S
Bargagna
Marino
M
Domenici
Ranieri
R
Bendinelli
Mauro
M
D016000:Cluster Analysis; D018076:DNA, Complementary / Q000737:chemistry / Q000302:isolation & purification; D005260:Female; D015699:HIV Envelope Protein gp120 / Q000235:genetics; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission* / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics; D010802:Phylogeny; D012367:RNA, Viral / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
D018076:DNA, Complementary; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D012367:RNA, Viral