You implied they don't cause gluten problems because the science community thinks GMO's aren't bad (and I agree with the science community). Dala agreed with you on this.
The real reason GMO's can't be causing the gluten problem is simply because there are no GMO cereal grains grown in the United States.
My comment was an indication of the foolishness of your lumping together people who are concerned about climate with people concerned aobut GMOs, particularly since the first is a scientifically valid position and the second is not.
The real reason that GMOs are not causing the gluten problem is that there is no biological mechanism by which they can do so, whether in the USa or any other country.