GM squash has unintended environmental consequences
New research indicates that GM virus-resistant squash may have unintended consequences for the squash and its wild relatives. Does it really matter and are the risks any bigger for conventional crops with similar traits?
GM squash has unintended environmental consequences
New research published in the PNAS this week indicates that GM squash engineered to be resistant to debilitating viruses may have unintended consequences on the fitness of the squash and its wild relatives, should it outcross with them. See link on GNTIS site
In a nutshell, the research found that cucumber beetles, a pest of squash, much prefer to munch on healthy squash plants as opposed those riddled with virus, which means if virus is present the GM squash will the preferred option for these beetles. Trouble is these beetles have a habit of delivering bacterial wilt disease to the squash, which can affect the quality of the crop.
That is one unintended consequence. The other is the unknown effect it might have in the environment, should the transgene (the virus-resistant gene inserted into the GM squash) get into the wild relatives of the squash, which the researchers think may have already happened.
The implications of this on the environment outside the well-tended paddock (field) is unknown as pointed out by the paper’s authors: “a full understanding of the combined effect of these forces on the fitness of an escaped transgene may not be apparent without the context of the complete ecological community.”
Should their research hold up to scrutiny its will be interesting to see how it affects future research and regulation. This will be especially relevant to Australian research trying to develop transgenic cereals and pastures that are resistant to drought, frost, salinity and other abiotic stresses. But as part of this research, it is necessary to find out if there are any wild relatives that such grasses or crops might cross with as as indigenous species suddenly endowed with the ability to withstand salinity might see it encroach into new and unwanted environments.
OK, checking this out before releasing such crops commercially is just sensible science. But the there is also considerable research going on to develop the same traits in crops using non-GM methods. The risk is the same that these crops may transfer their stress-related genes to indigenous species with the same environmental implications. Should we regulate the breeding of all crops in a similar fashion? What if the transgenic squash in question had been developed by conventional means, would anyone have bothered to do the research to see if it transferred it virus-resistant genes to wild populations?
Jason Major