Discovery and Characterization of Novel Signatures from the Ricinus communis L. (Castor Bean) Genome

Abstract : Given the infamous toxicity of ricin and the industrial usefulness of castor oil, there is a surprising lack of information about the genetic diversity of the species that produces both, the castor bean plant (Ricinus communis L.). The extent of DNA sequence variation in the gene that encodes ricin (preproricin) is also poorly understood. This lack of knowledge hampers the ability to make effective assays, or to associate ricin toxin from sites of release with suspect production labs. Without this basic genetic understanding, assays for ricin may not positively react with genomic DNA from R. communis derived from any source. We are remedying this shortfall by pursuing a genetic characterization of members of R. communis collected from around the world. Preliminary data from the amplification and sequencing of preproricin genes from 63 members of this collection indicate the presence of a large number of nucleotide polymorphisms, and the possible presence in some varieties of a previously unreported, shorter-length paralog of the preproricin gene.