Nucleic Acids Res. 1988 Oct 25;16(20):9677-86

Clark JM

Novel non-templated nucleotide addition reactions catalyzed by procaryotic and eucaryotic DNA polymerases.

Terminal desoxynucleotidyl transferase activity of DNA polymerases, including AMV reverse transcriptase. Preference for adding As. ‘We cannot exclude the formal possibility that some of these latter events, particularly the addition of dCMP by AMV reverse transcriptase, involve the use of coding information made available as a result of a transient misalignment of the primer/template substrate.’