Producing, cataloging and classifying sequence tags

Abstract

The described method provides, methods, and kits to produce, identify, catalog and classify a comprehensive collection of nucleic acid targets produced from a nucleic acid sample. The method, referred to as Cataloging and Classification of Sequence Tags, involves generating a set of target nucleic acid fragments; coupling the target nucleic acid fragments to a nucleic acid bridge comprising, for example, two or more primer binding sites and two recognition sites for cleavage at a site offset from the recognition site to the fragment's end; and cleaving the fragments to generate chimeric nucleic acids of known length. The nucleic acid bridge is thus disposed between the two nucleic acid fragments in the chimeric nucleic acid. The resulting duplex nucleic acids comprise a set of sequence tags (i.e., by amplification using universal primers), comprising an addressable portion, a target nucleic portion and a portion of the nucleic acid bridge. Single-stranded or partial duplex sequence tags may be captured by coupling to a complementary capture probe. Capture probe-sequence tag hybrids, may be detected employing a labeled detector probe. The method allows a complex sample of nucleic acids to be cataloged in a reproducible and sequence-specific manner. The method further provides methods for analysis of the above sample to classify the sequence tags; determine the presence and relative amounts of sequences of interest; derive expressed genes signatures and differential gene expression signatures; and identify putative expressed sequence tags (EST).