Digestive stability and acute toxicity studies of exogenous protein in transgenic rice expressing lysine-rich fusion proteins

Evaluating exogenous protein expressed in transgenic crops is one of the most effective methods of assessing the safety of transgenic plants. The objective of this study was to assess the food safety of genetically modified (GM) rice containing a lysine-rich fusion protein gene (transgenic GL gene rice) by in vitro digestion and acute toxicity testing of exogenous protein, according to the national standard of the People’s Republic of China. The exogenous protein was rapidly degraded in the simulated gastric and intestinal fluids. In the acute experiment, the exogenous protein was injected into Institute of Cancer Research (ICR) mice via the tail vein at a dose of 438 mg kg^?1 body weight. No adverse effects on animal behavior or mortality were observed during the following 15-day period and there were no significant biological changes in body weight, serum biochemistry parameters, relative organ weights or histopathological examinations, compared with the control group. Therefore, exogenous protein in transgenic GL gene rice has a low potential allergenicity or toxicity risk.