The present invention relates to a method of preparing a cDNA molecule which includes: contacting an RNA molecule, in the presence of dNTPs, with a non-LTR retrotransposon protein or polypeptide having reverse transcriptase activity under conditions effective for production of a cDNA molecule complementary to the RNA molecule, the contacting being carried out in the absence of a target DNA molecule of the non-LTR retrotransposon protein or polypeptide; and isolating the cDNA molecule. The preferred non-LTR retrotransposon protein or polypeptide is an R2 protein or polypeptide.