Regulatory policy on genetically modified breeding stack in key countries and the current status in Korea.

With an increasing interest and demand for biotechnology crops in agriculture worldwide, genetically modified (GM) breeding stacks produced by conventional breeding of previously approved GM single events remain popular for farmers in GM crop cultivation countries. However, regulations on stacks vary in each country. Currently, Korea requires approval for all breeding stacks intended for cultivation. To determine whether the stack is subject to a full safety assessment as a new GM crop, molecular characterization, protein expression, composition analysis, and agronomic characterization data are required. Korea's regulatory policy on stacks has not adopted the high-covers-low concept; therefore, subcombinations of already approved higher combination events are subject to breeding stack review if any subcombination was purposefully bred for cultivation use. This review will help promote the efficient management of GM breeding stacks in Korea in the future.