The average Δ87GAD65mut expression level in red beet leaves was 201.4 ± 29.3 μg/g FLW, which is sufficient to commence the development of a T1D oral vaccine that will be required in large amounts, ranging from micrograms per day per animal for preclinical studies in mouse models of T1D through to milligrams per day per subject for human clinical trials, as previously reported for recombinant oral insulin (Polanski et al., 1997; Skyler et al., 2005). The gene discussed is INS; the disease is type 1 diabetes mellitus.