Analysis of the integrase gene from HIV-1 positive patients living in a rural area of west Cameroon

Major mutations associated with HIV-I integrase inhibitors (INI) resistance are rare in INI-naive patients. However, polymorphisms at positions that may influence the genetic barrier and/or drive the selection of specific INI resistance pathways are common in HIV non-B subtypes. The aim was to evaluate the presence of natural polymorphisms and/or INI resistance mutations in HIV-1 non-B subtype samples obtained from INI-naive patients living in rural west Cameroon. Thirty-three HIV-1 non-B samples were obtained from INI-naive African women and, as controls, 15 samples of HIV-1 subtype B were obtained from antiretroviral-naive Italian patients. The integrase gene was amplified and sequenced using Trugene Core Reagents. Several amino acid positions in B and non-B subtypes were found to be polymorphic. Interestingly, two patients infected with the CRF02_AG subtype had the resistance mutations N155H and E157Q/E and 12% of African samples had an amino acid substitution at position 143. Silent mutations leading to a higher increment of genetic barriers were detected at 140 and 151 positions in non B-subtypes. Although most polymorphisms may have little effect on INI susceptibility, the IN gene variations found in the present study should be taken into consideration as they may facilitate or delay the emergence of variants fully resistant to INIs.