People get muddled up between science and technology. Genetics is science, and it's brilliant. GMOs are technology, and some of them are dodgy. Then there's advocacy, things like saying that there is "substantial equivalence" between GMOs and natural food, and that is simply disingenuous.
GMO food should be labelled so that those who choose not to eat it have the freedom so to do. This is also important for science, bcz to study the health effects of GMOs you need a population who are not exposed to them. Like you need non-smokers to find out about the health effects of smokers.