Abstract: The present invention relates to the isolation of Jatropha curcas curcin genes and tissue-specific promoters and to the production of curcin-deficient Jatropha plants. More specifically, the present invention relates to the isolation of Jatropha curcas Curcin 1, Curcin 2 and Curcin 2 A. The present invention further relates to of the Curcin 1, Curcin 2 A and Curcin 2 genes and more particularly to tissue specific promoters of the Curcin 1 and Curcin 2A genes. The present invention further relates to production of curcin-deficient transgenic jatropha plants by using RNAi technology to suppress curcin gene expression.