A PCR variation that permits specific amplification of the sequence from a single known internal sequence to the end of the fragment. The source DNA is cleaved by a restriction endonuclease that leaves an overhang, by which the fragments are ligated to a compatible universal synthetic oligonucleotide duplex called a vectorette. The vectorette is engineered with a central mismatched sequence, and the vectorette primer is identical to the sequence on the vectorette strand that becomes ligated to that fragment strand which can bind a second primer that is complementary to the known internal sequence of the fragment. The binding site for the vectorette primer is created only when the internal primer is extended to the end of the vectorette. This avoids duplication of the vectorettes attached to all other restriction fragments. A refinement is splinkerette PCR, in which the primers are designed to form hairpin structures, which decreases the danger of non-specific priming.