The use of synthetic oligonucleotides as hybridization probes. II. Hybridization of oligonucleotides of mixed sequence to rabbit β-globin DNA

摘要

Two oligonucleotides 14-bases long were synthesized, one complementary to rabbit β-globin DNA (RβG14A) and the other with the same sequence except for a single base change (T for C) (RβG14B) Hybridization conditions were established such that RRβG14A would hybridize to globin DNA while RβG14B would not. We also synthesized a mixture of 13-base long oligonucleotides (RβG13Mix), representing eight of the possible coding sequences for amino acids 15–19 of rabbit β-globin. One of the eight is complementary to globin DNA. RβG13Mix was found to hybridize specifically to globin DNA under conditions where oligonucleotides forming single base pair mismatches do not. Furthermore, RβGl3Mix was shown to hybridize specifically to colonies containing a plasmid with a globin DNA insert. These results are discussed with respect to a general procedure for screening recombinant clones for those containing DNA coding for a protein of known amino acid sequence.