PERFORMANCE OF THE NEW VIROSEQ ™ HIV-1 GENOTYPING SYSTEM (VERSION 2) WITH GROUP M SUBTYPE PANEL AND WITH SUBTYPE B CLINICAL RESEARCH SAMPLES AT TEST SITES

The new Applied Biosystems ViroSeq HIV-1 Genotyping System (HGS) was formally released in April 2000 for Research Use Only. The ViroSeq kit provides a contiguous sequence of the protease gene and codons 1–315 of the reverse transcriptase gene. In this kit, a number of changes were made to improve the robustness and sensitivity of the assay. These changes include the use of a single RT primer, a new PCR primer, improved formulations for both the RT and PCR reagents and the AmpErase UNG contamination control system. The UNG system prevents the possibility of false genotyping results due to contamination by previous PCR reactions. In addition, the ViroSeq Sequencing module utilizes the Applied Biosystems BigDye terminator chemistry and 6–7 sequencing primers to obtain double coverage sequence for the protease and first 315 codons of the reverse transcriptase genes. This new kit was tested internally and externally to determine the performance of the kit with subtype B and non-subtype B samples. Performance was evaluated relative to the ability to generate sufficient PCR product for sequencing and to generate a consensus sequence which could be used to identify mutations which have been reported by the Los Alamos HIV1 database [1] as being correlated with anti-HIV-1 drug resistance.