A Built-In Strategy to Mitigate Transgene Spreading from Biotech Corn

One of the major concerns about planting biotech crops is the spread of transgenes through cross-pollination from biotech to conventional farms. Aside from that, transgenes can also escape through mixing during sowing, harvest, and trade. In a study conducted by scientists from Zhejiang University in Hangzhou, China, a built-in containment method was developed to mitigate transgene spreading in corn. In this containment method, an RNAi cassette for suppressing the expression of the nicosulfuron detoxifying enzyme CYP81A9 and an expression cassette for the glyphosate tolerant EPSPS gene G10 were constructed and transformed into corn through Agrobacterium-mediated transformation.

The biotech corn plants generated showed sensitivity to nicosulfuron and resistance to glyphosate, which exactly the opposite of the characteristics of conventional corn. Furthermore, field tests showed that biotech corn plants with silenced CYP81A9 could be killed by applying nicosulfuron at 40 g/ha, which is the recommended dose for weed control in cornfields. The results of the study suggest that this built-in containment method for controlling the spread of corn transgenes is effective and easy to implement.

Read the results at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0081645.