Analysis of expressed sequence tags from human brain cDNAs

A major goal of this laboratory is to identify as completely as possible the expressed gene complement of the human brain. Toward this end, the authors have collected partial sequence data (expressed sequence tags, ESTs) from over 6,000 human brain cDNA clones using automated fluorescence-based sequencers. Over 80% of these sequences represent genes not previously described in humans and up to one third may represent coding sequences with no matches in the existing databases. Database searches have identified several hundred clones with significant similarity to known genes, including novel genes similar to Notch/Tan-1 and the Drosophila discs-large tumor suppressor, a new neurotransmitter transporter gene, a new member of the multidrug resistance gene family, new members of the Ca++-ATPase, ADP-ribosylation factor, alpha-actinin, and neural cell adhesion molecule gene families, and at least seven new C2-H2 zinc finger proteins. Various brain libraries contain an excellent diversity of clones, with judicious screening of a relatively small number of highly and moderately represented sequences, large numbers of different genes can be tagged. Thus, normalization is not required at this stage to reduce the redundancy of sequencing. The authors have constructed a relational EST database for storage and integration of cDNA sequence analysis data. ESTmore » sequence data and cDNA clones are available to researchers through GenBank and the American Type Culture Collection.« less