Determination of human immunodeficiency virus type 1 subtypes by a rapid method useful for the routine diagnostic laboratory.

The existence of human immunodeficiency virus type 1 (HIV-1) subtypes has many important implications for the global evolution of HIV and for the evaluation of pathogenicity, transmissibility, and candidate HIV vaccines. The aim of this study was to establish a rapid method for determination of HIV-1 subtypes useful for a routine diagnostic laboratory and to investigate the distribution of HIV-1 subtypes in Austrian patients. Samples were tested by a subtyping method based on a 1.3-kb sequence of the polymerase gene generated by a commercially available drug resistance assay. The generated sequence was subtyped by means of an HIV sequence database. Results of 74 routine samples revealed subtype B (71.6%) as the predominant subtype, followed by subtype A (13.5%) and subtype C (6.8%). Subtypes E, F, G, and AE (CM240) were also detected. This subtyping method was found to be very easy to handle, rapid, and inexpensive and has proved suitable for high-throughput routine diagnostic laboratories. The specific polymerase gene sequence, however, must be existent.