Misunderstandings Part 3 - GM crops

There are many topics of public interest which are blown out of proportion, or presented horribly inaccurately due to the media. We've all just seen the recent furore caused by the Daily Express' handling of the Madeleine McCann case. We're all aware of how much more attention is given to allegations of paedophilia when they're directed at teachers or scout leaders and consequently how much the media likes to exaggerate tales of paedophilia within the priesthood (which is not to say that it doesn't happen, or that it's not incredibly serious: but that they blow it massively out of proportion). Another issue, possibly not seen as so serious: in that it doesn't destroy lives - but actually no less important to my mind is that of GM crops.


By 2050 it is estimated that the world population will reach 8 or even 9 billion people. Currently, there are around 6 billion of us. We're actually looking at a 30% increase in just 40 years. Crazy! We already struggle to feed the world. Yes there are grain mountains and milk lakes... but even if they were used we would still be pushing it somewhat to feed each and every one of the 3 billion people currently living on less than 2 dollars a day. Or even to just help the 1.6 billion who live on less than a dollar a day.


An increase in people means an increase in food needed: and right now we're looking at a major deficit. There are many reasons to take GM farming seriously, but the prospect of a starving world provides more motivation than most things.


So what does GM mean?

Genetic Modification or Genetic Engineering is the insertion (or deletion) of genes into a plant genome (the package of DNA that the plant uses as an instruction manual for building proteins). There are two main methods for this: one is using a plasmid, taken up by Agrobacterium tumefaciens - a plant pathogen, which creates a tumour and adds its own DNA to the plant's; or you can fire it in using a special gun with golden bullets coated in DNA.



But surely anything could happen?

Well, in the most science fiction world possibly yes it could. But the fact is that we're not just adding genes at random - we're selecting useful genes for their function, and adding them. You're giving the plant an extra set of instructions and all it can do is follow them. So if you give it the gene for a blue pigment all it can do with that gene is make that blue pigment. It can't magically grow legs and run away because the gene doesn't tell it to do that.

In many ways GM is actually "safer" than conventional selective breeding. In the past we've mixed 2 whole different genomes (imagine mixing wheat and rice - although really we're breeding species more closely related than those) whereas now we are taking one single gene, the function of which we already know, and only adding that.


But is it morally ok to mix and match genes from different organisms?

Well to start with, the genes aren't usually from vastly different organisms. In the olden days we used to find a plant with a good trait (say a higher yield) and then breed the plants to move the gene. The same thing is done now, only with GM. As plants have been bred for yield and size, often useful genes such as disease resistance have been lost, so GM is used to put them back. This has been done with e.g. wild wheat and Inca wheat with domestic wheat.

Secondly, unlike most animal species, plant species are actually relatively easy to hybridise. We've been creating plants that came from 2 different plants to begin with for years and years anyway - most of the Brassicas (oil seed rape, cauliflower, cabbage, broccoli, mustard etc) are either hybrids themselves, or have been hybridised to make more crops. This way is just faster.

Thirdly, genes from a completely different organism (such as the genes from Erwinia in golden rice) are actually very rare. Normally we're switching genes between plants, which is far less strange if you ask me.

Finally: if you're going to talk about moral obligations, how morally right is it to supress a technology that could safely feed the entire world. Forget about giving up meat, and irrigation, and all the other ways we're fighting tooth and nail to get enough grain to feed the world. Hand me some GM and off we go. Same goes for fighting Vitamin A and Iron deficiency in Asia with specially developed rice strains.

Is it morally questionable to mix and match species?
Possibly - although we've done the same thing with domestication for the last 10 000 years.

Is it morally questionable to let 4 billion people starve?
I'd hazard that at a resounding yes, personally!

Ok so it's rare. What about those rare cases when it does happen? Couldn't the gene escape? Could it be passed to humans?

No. Absolutely not. At all. Think about a carrot: it's orange because it has genes for carotenoids (a type of antioxidant). No matter how many carrots you eat you will not pick up that gene yourself and start making carotenoids, and turn orange. The only way to get those genes into a human would be for you to have sex with the carrot and have fertile offspring. Not really gonna happen.

What about plants of the same species that aren't GM?

That is actually one of the very few real risks, and it's why GM crops have to be a certain distance from non-GM crops of the same species. Even then, it depends a lot on the plant. Something like maize has heavy fat pollen that literally gets about 10m before it falls on the floor. It's why we plant maize in fat squares, not long strips. Unless there's a mini-hurricaine that pollen isn't getting anywhere near the next field!

And here ends the FB summary to GM