The exponential rise in sequence data from diverse organisms continues to enhance the power of comparative approaches to understanding protein function. The group has previously developed alignment-based tools to facilitate this analysis, by brining into play position-based strategies for predicting deleterious mutations and variants in organisms as diverse as bacteria and humans. This project aims to apply a position-based approach to identifying deleterious lesions in reverse genetics project and in the analysis of natural variants. A general reverse genetics strategy has been developed that uses chemical mutagenesis and screening for point mutations,, and applied to establishing a resource for the Arabidopsis community. The proposed tools should enhance functional genomics approaches in both academia and industry. Knowledge gained from function genomics is valuable for its own sake, but also has the potentials of contributing to broader environmental welfare.