Based on the investigators previous study, seventy-four of 786 HIV-1 isolates (9.4%), collected between 1999 to 2006, harbored one or more primary mutations associated with antiretroviral resistance to reverse-transcriptase inhibitors (RTIs) or protease inhibitors (PIs) in naïve patients. However, the drug resistance profiles for the HIV-1 integrase gene is unclear. Three objectives are proposed: