Searching the dbEST Database

The accumulation and analysis of expressed sequence tags (ESTs) are now an important component of genome research (1 ). An EST is a fragment of a sequence from a cDNA clone that corresponds to an mRNA. ESTs have applications in the discovery of new human genes, mapping of the human genome, and identification of coding regions in genomic sequences. Although the EST sequences are available in the EST section of both EMBL (2 ) and GenBank (3 ) nucleotide sequence databases, the National Center for Biotechnology Information (NCBI; National Institutes of Health, Bethesda, MD) has created a specialized database in which specific information related to these data can be found. This chapter describes this database and the different ways it can be accessed.