To generate "5'-end" partial cDNA clones using classic RACE, the first-strand products are generated by reverse transcription (primer extension) from a known gene-specific primer (GSP-RT).  Then, a poly(A) tail is appended using terminal deoxynucleotidyltransferase (Tdt) and dATP.  Amplification is carried out using three primers.

Protocol: 5'-End cDNA Amplification Using Classic RACE Protocol