GM plants differ from non-GM parents in unintended ways – and that goes for GM gene-edited plants too

Following a recent podcast interview we were asked whether there is any solid scientific research looking at how gene expression or molecular composition in genetically modified (GM) plants differs from conventionally bred plants. As this is an interesting and important question, we thought it would be worth exploring the evidence for how GM plants differ from conventional ones.

First-generation GMOs

There is good evidence of unintended changes between older-style, first-generation (“transgenic” – involving random insertion of foreign gene(s)) genetically modified organisms (GMOs) and their non-GMO counterparts. For example, a review of “omics" molecular profiling studies by Benevenuto et al (2022) concluded: “Several altered metabolic pathways have been found in the comparative omics studies assessing unintended effects in GM crops.”

This review includes the work of Prof Michael Antoniou and colleagues on glyphosate-tolerant NK603 GM maize vs its non-GM isogenic (with the same genetic background, but without genetic modification) parent. This study found that there were major protein and biochemical (metabolite) differences between the GM and non-GM maize and that these differences were due to the GM transformation process, leading the...