Changes in the human immunodeficiency virus p7-p1-p6 gag gene in drug-naive and pretreated patients

Resistance to antiretroviral agents often results from mutations within the human immunodeficiency virus (HIV) pol gene. Moreover, insertions within the p6 gag pol region have recently been found to be involved with resistance to nucleoside analogs. Overall, we found that 21% of 156 specimens collected from HIV-infected individuals (17.6% from 74 drug-naive patients and 24.4% from 82 pretreated patients) harbored these insertions. Insertions around the KQE (Lys-Gin-Glu) motif were found in 12.2% of the pretreated patients but in none of the drug-naive subjects (P = 0.002). In contrast, insertions around the PTAP (Prof-Thre-Ala-Prol) motif were seen at similar rates (similar to15%) among drug-naive and pretreated patients, which supports the idea that they may be natural polymorphisms.