The potential allergenicity of Bar, Barnase, and Barstar recombinant proteins expressed in genetically engineered mustard for pollination control in plant breeding was evaluated for regulatory review. To evaluate the potential allergenicity of the Bar, Barnase and Barstar proteins amino acid sequence comparisons were made to those of known and putative allergens, and search for published evidence to the sources of the genes using the AllergenOnline.org database.