Controversy on Transgenic Xianyu 335

Is Xianyu 335 a genetically modified corn? According to the announcement of China Agriculture Department, Xianyu 335 is a hybrid corn bred by American Pioneer Company. Its female parent is PH6WC, and its male parent is PH4CV, all of which are selfed by Pioneer Company.

The patent description document of PH4CV, the parent of Xianyu 335, mentioned transgene, which means that anyone who uses PH4CV for transgenic cultivation must be authorized by the patentee, not that the variety is transgenic. In fact, the first sentence of the patent specification document indicates that PH4CV is an inbred variety. The International Herald Tribune reported that PH4CV was a genetically modified variety, which was misinterpreted by the reporter.

Some internet content said that "an organization of the Ministry of Environmental Protection" detected the existence of 35S promoter in Xianyu 335, so it was unrealistic to conclude that Xianyu 335 contained transgene. First of all, the statement that the agency "detected 35S" is only found in blog articles, which is groundless. Secondly, to take a step back, even if an institution does detect the 35S promoter, it is still uncertain whether it is transgenic or not. It is necessary to exclude mosaic virus infection and detect characteristic genes (see GB/T 19495.4-2004). In fact, the BT gene has 3800 bases, and the promoter has only more than 200 bases. It is not only against the national standard to judge genetically modified by only 35S, but also makes a joke that "sesame seeds can see watermelon but not watermelon".