Please see this journal article and the review in Nature Biotechnology February 2004. I offhandedly comment that the reason I don't eat GMO's is mainly that I think my natural gut bacteria may acquire the altered gene which codes for an insecticide (toxin) or an herbicide resistance gene (toxin), has a super-promoter (unlimited replication), and an antibiotic resistance gene. Don't forget that the code transfer isn't stable so who knows what unique chemicals these bacteria produce? Anyway its been hard to locate these articles, so thank you,!