The fidelity of 3' misinsertion and mispair extension during DNA synthesis exhibited by two drug-resistant mutants of the reverse transcriptase of human immunodeficiency virus type 1 with Leu74→ Val and Glu89→ Gly.

Reports on the implication of the relatively low fidelity of DNA synthesis characteristic to the reverse transcriptases (RT) of the AIDS-causing viruses, as a dominant factor that contributes to the genetic hypervariability of the viruses. Mutational studies aimed at identifying amino-acid residues involved in affecting the fidelity of DNA synthesis by the enzyme; Possible linkage between the capacity of an enzyme to incorporate a nucleoside analog instead of the correct dNTP leading to drug sensitivity.