Soybean (Glycine max L. Merrill) is one of eight major allergenic foods with endogenous proteins identified as allergens. To better understand the natural variability of five soybean allergens (Gly m 4, Gly m 5, Gly m 6, Gly m Bd 28k, and Gly m Bd 30k), validated enzyme-linked immunosorbent assays (ELISAs) were developed. These ELISAs measured allergens in 604 soybean samples collected from locations in North and South America over five growing seasons (2009-2013/2014) and including 37 conventional varieties. Levels of these five allergens varied 5-19-fold. Multivariate statistical analyses and pairwise comparisons show that environmental factors have a larger effect on allergen levels than genetic factors. Therefore, from year to year, consumers are exposed to highly variable levels of allergens in soy-based foods, bringing into question whether quantitative comparison of endogenous allergen levels of new genetically modified soybean adds meaningful information to their overall safety risk assessment.
Keywords: ELISA; allergenicity; natural variability; safety assessment; soybean.