Incremental generation of an EST set for the analysis of scrapie pathogenesis

As part of a functional genomic study of scrapie pathogenesis we have generated a complex non-redundant microarray from several tissues by the selection of unique clones and the incremental augmentation of the expressed sequence tag sets. The base set of about 15,000 expressed sequence tags had minimum redundancy and originated from bovine brain. The aim was to augment this set with clones from scrapie-infected brain and spleen and uninfected spleen with minimum redundancy. This was achieved by macroarray hybridization to identify unique sequences in the ovine library. Quality sequence of 4052 unique sheep clones were obtained from the sequencing of only 5000 which have been submitted to the dbEST database at GenBank.