How many commercial transgenic crops are the creation of single amino acid changes in single proteins? This would be the most conservative type of genetic modification possible, involving even less change replacing one gene from another organisms analogous gene or adding a single new gene from another organism.

Expert response from Ray Dobert, Ph.D.

Global Biotech Policy Manager, Bayer Crop Science

Monday, 28/09/2015 14:00

I am not aware of any commercialized transgenic crops that have a single amino acid change to a single protein.  The closest example would be the glyphosate-tolerant corn, event GA21, which was developed by changing two out of the 445 amino acids in the corn EPSPS protein. This change resulted in 60,000-fold reduced sensitivity of the enzyme to the herbicide compound glyphosate.  

If you are basing the degree of conservativeness on changes to the protein, an even more conservative change would be one where no new protein is made at all. This is the situation for several transgenic crops that use RNA interference (RNAi) technology to silence a trait normally produced by the plant, or use it to protect the plants against viruses or insects. In the case of RNAi technology, no additional protein is produced at all or amino acid changed. Genetically modified crops using RNAi technology include virus-resistant squash, papaya and plum, non-browning apple, reduced lignin alfalfa and soybeans with improved oil composition.