DNA tailing without terminal transferase.

Tailing of DNA with terminal transferase is a technically demanding, but essential step in full-length cDNA cloning procedures*•^. It is also an essential step of a poly(dA) affinity labelling technique, which has been used to select families of partial restriction fragments on oligo(dT)cellulose^•*. In order to bypass the need for transferase in the latter technique, we made a simple modification of DNA-linker design, to produce a "tailing-adapter" which may have broader applications. The top strand of the tailing-adapter (A), was synthesised and 5' phosphorylated with T,j-kinase. It was then