Identification of insertion mutations in HIV-1 reverse transcriptase causing multiple drug resistance to nucleoside analogue reverse transcriptase inhibitors.
OBJECTIVE
A novel 2-amino acid insertion between codons 69 and 70 of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) which confers multiple drug resistance has recently been reported. Independently, we have identified similar insertion mutations in Japanese hemophiliacs and attempted to analyze their emergence in conjunction with therapy regimens and their contribution to drug resistance using recombinant technology.


METHODS
The plasma and peripheral blood mononuclear cells (PBMCs) of 348 HIV-1-infected hemophiliacs were screened for HIV-1 RT mutations relevant to nucleoside analogue inhibitors and isolating viruses. Contribution of each insertion to drug resistance was studied by introducing the mutations into a T-cell line-tropic NL4-3 infectious clone and testing the drug susceptibilities of the recovered virus.


RESULTS
Insertion of the 2-amino acid residue was found in 4 of the 348 cases and was strongly associated with prolonged chemotherapy with zidovudine (AZT) and didanosine (ddI). The virus isolated from 1 of the 4 cases possessed the same insertion. Characterization of these virus and the recombinant NL4-3 with the insertion strongly suggested that the insertion caused resistance not only to AZT and ddI but also to lamivudine (3TC) and zalcitabine (ddC).


CONCLUSIONS
A 2-amino acid insertion between codons 69 and 70 of RT was detected in 4 of 348 (1.1%) Japanese hemophiliacs and was found to be associated with multiple drug resistance to nucleoside analogue RT inhibitors.
National institute of Infectious Diseases AIDS Research Center, Tokyo, Japan. wsugiura@nih.go.jp
W
W
Sugiura
M
M
Matsuda
Z
Z
Matsuda
H
H
Abumi
A
A
Okano
T
T
Oishi
K
K
Moriya
Y
Y
Yamamoto
K
K
Fukutake
J
J
Mimaya
A
A
Ajisawa
M
M
Taki
K
K
Yamada
Y
Y
Nagai
D000595:Amino Acid Sequence; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology* / Q000627:therapeutic use; D019556:COS Cells; D015224:Dideoxynucleosides / Q000494:pharmacology* / Q000627:therapeutic use; D004352:Drug Resistance, Microbial / Q000235:genetics; D018432:Drug Resistance, Multiple / Q000235:genetics*; D005838:Genotype; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy / Q000821:virology*; D054303:HIV Reverse Transcriptase / Q000235:genetics*; D015497:HIV-1 / Q000201:enzymology* / Q000235:genetics; D006467:Hemophilia A / Q000150:complications; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D017386:Sequence Homology, Amino Acid
D019380:Anti-HIV Agents; D015224:Dideoxynucleosides; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase