[Studying on the prevalence and mutation pattern of N348I which related to the resistance of HIV-1].

Objective: To elucidate the prevalence and the mutation pattern of N348I that related to the resistance seen in the AIDS patients, in China.

Methods: Partial pol gene of HIV-1 comprising of full protease (PR) and reverse transcriptase (RT) was obtained from plasma samples of therapy-failure individuals (n = 614) and therapy-naive individuals (n = 619) by using reverse transcription polymerase chain reaction (RT-PCR). 1233 sequences were then submitted to the HIV-1 drug resistance database of the Stanford University to analyze the prevalence and the emergence pattern of N348I.

Results: The prevalence of N348I was 6.5% in the therapy-failure patients and 0.8% in the naive individuals, respectively. The prevalence of N348I was more popular among those patients whose ART regimens containing zidovudine (AZT or ZDV) than those without AZT in regimens (14.1% vs. 4.7%, χ² = 10.21, P < 0.01). N348I always emerged, and combined with others mutations among patients of ART, whose frequencies were: 85.0% in combination with thymidine analog mutations (TAMs) and 52.5% with M184V/I, respectively.

Conclusion: N348I was somehow prevalent in the therapy-failure patients when using the first-line antiretroviral drugs, and it emerged as unique patterns. This study laid the ground in improving the technology of drug resistance genotypes detection and providing theoretical basis to study the mechanism of resistance and the law of molecular evolution.