There is no evidence that producing a new crop variety using GM techniques is more likely to have unforeseen effects than producing one using conventional cross breeding.
Concerns have been expressed that simply inserting new DNA into a plant genome by GM, might have unpredictable consequences. However, as our knowledge of genomes has increased it has become clear that similar insertion events occur frequently in all plants. For example, some bacteria and viruses insert new genes into the genomes of plants that they infect. We have also discovered that plant genomes contain many so-called “jumping genes” that move around the genome, re-inserting themselves in different places. We also know, from studying the genomes of different members of the same species, that gain and loss of genes within species is very common too.
We have also discovered that plant genomes contain many so-called ‘jumping genes’ that move around the genome, re-inserting themselves in different places.
Because of these processes, all new crop varieties, however they are produced can include genes inserted in new unknown places in the genome and new genes that may not have previously been in the food chain or come from non-plant species. This means that there may occasionally be unforeseen consequences from both GM and non-GM crop varieties.
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