Strand selections resulting from the combined template-independent DNA synthesis and clamp activities of HIV-1 reverse transcriptase

► The reverse transcriptase (RT) of HIV-1 has a non-templated addition activity. ► RT has also a clamp activity that allows template switches while synthesizing DNA. ► This clamp depends on a complementarity between the primer tails and template strands. ► We studied how parameters of these two activities affect the RT's DNA strand switches. ► dNTP bias, proper acceptor strands presence and the duplex stabilities were studied.