GM oilseeds for Britain?

This year in Britain, we heard there’d be no GM (genetically modified, genetically engineered, biotech) crops. It didn’t last. A new GM crop might soon be field-tested here. Eventually this crop might reduce pressure on overfished seas. A land plant to conserve the sea? Yes, really.

Approval hasn’t yet been given but I think the field tests will happen. The well-respected Rothamsted Research (‘where knowledge grows’) has applied for permission to test an oilseed plant that grows omega-3 fatty acids. You can see more at the Rothamsted information page about this new GM oilseed.

You might know that fats and oils are glycerides built from glycerol and fatty acids. Some fatty acids are essential in human food because our bodies need them, but can’t make them. The essential fatty acids include omega-3 and omega-6. Omega-3 fatty acids include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Here’s a list of non-GM foods which give us omega-3 fatty acids. Items on that list, likely to appear as raw ingredients or value-added products in my own grocery basket, include oily finfish such as Atlantic salmon (Salmo salar), brown trout (Salmo trutta), rainbow trout (Onchorynchus mykiss) and skipjack tuna (Katsuwonus pelamis), and shellfish such as brown crab (Cancer pagurus), blue mussels (Mytilus edulis) and oysters (Ostrea edulis). These seafoods are sources of EPA and DHA.

My groceries might also include oilseeds such as walnuts (Juglans regia) and hazelnuts (Corylus avellana). Those contain omega-3 fatty acids but they don’t contain EPA or DHA.

People like me, in rich countries, are buying oily finfish partly because we’ve learned about the essential fatty acids. It tastes good too. A lot of the oily finfish in our grocery baskets is from fish farms, except the skipjack tuna which is always wild-caught.

Aquaculture is important worldwide, including in Europe. This can put pressure on wild stocks. Small wild marine fish eat algae and bioaccumulate omega-3 fatty acids. People catch those small fish and turn them into fishmeal and fish oil to make pellets for aquaculture. The pellets feed carnivorous, oily finfish such as the farmed species that I said feature in my grocery basket. So as we eat more and more farmed fish, we’re exploiting more and more wild fish. This isn’t sustainable.

There are some obvious responses that don’t require GM. We could farm algae and eat them or use them as ingredients in fish food.

We could grow, trade and eat more walnuts, hazelnuts and other omega-3 oilseeds such as flax (linseed, Linum usitatissimum), butternut squash (Juglans cinerea), hemp (Cannabis sativa) and pecan (Carya illinoinensis). But since those oilseeds don’t contain EPA or DHA, you’d need to be more of a nutritionist than I am to judge whether they make adequate substitutes for oily finfish.

Could those non-GM responses be used in cost-effective ways? Maybe. But biotech offers another possible solution. It offers the new GM crop likely to be field-tested at Rothamsted. You can scroll down this blog post and follow a link to watch a film explaining why this is better than any non-GM plant.

Until the new GM crop gets a name, I’ll call it ‘Omega Camelina’. It’s a false flax (Camelina sativa) engineered so that its seeds contain EPA and DHA. C. sativa is an oilseed crop related to oilseed rape (rapeseed, canola, Brassica napa). Those plants make useful oils but they don’t make EPA or DHA.

Here’s the science about Omega Camelina. Johnathan Napier and other scientists at Rothamsted used the bacterium Agrobacterium tumefaciens to insert genes from a marine alga called Ostreococcus tauri into C. sativa. They also put in tissue-specific promoters so that the fatty acids would end up in the plants’ seeds.

Prof Napier and his team say, ‘Currently, the primary dietary source [of EPA and DHA]… is marine fish; however, the increasing demand for fish oil (particularly due to the expansion of the aquaculture industry, the major consumer of these oils) places enormous pressure on diminishing marine stocks… Such over-fishing and concerns related to pollution in the marine environment have triggered an urgent search for a completely new source of omega-3 [fatty acids]… any potential new source… should be both sustainable and capable of meeting any increased demand. An appealing approach… is metabolic engineering of a crop plant with the capacity to synthesize these fatty acids in seeds. The scalability of agriculture-based production systems, in conjunction with modest running costs, highlights the potential of transgenic plants as ‘green factories’… [C. sativa has] low input costs and [it’s relatively easy to engineer its genes.]’

You can watch this film of Prof Napier explaining Omega Carolina. He says that he’s annoyed because without GM, ‘plant oils can’t substitute for fish oils.’ They don’t have the kinds of omega-3 fatty acids we need. That pretty much destroys the claims about eating plant foods to get those essential nutrients.

The International Centre for the Acquisition of Agri-biotech Applications (ISAAA) is pleased about Omega Camelina because it could help marine conservation. What do you think?

About argylesock

I wrote a PhD about veterinary parasitology so that's the starting point for this blog. But I'm now branching out into other areas of biology and into popular science writing. I'll write here about science that happens in landscapes, particularly farmland, and about science involving interspecific interactions. Datasets and statistics get my attention. Exactly where this blog will lead? That's a journey that I'm on and I hope you'll come with me.
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7 Responses to GM oilseeds for Britain?

  1. Eqfe says:

    This is an interesting development. It’s certainly seems to be worth testing.

    • argylesock says:

      Yes. I haven’t yet seen any objections. When they come, I wonder whether they’ll be like the objections to potato Amflora – concern about the antibiotic resistance genes used in the Agrobacterim GM method.

  2. I think the issue with plant based omega-3 is that it needs to be converted by your body to DPA and EHA, and that’s an inefficient process. The same is true for some fish; but many fish are unable to convert the naturally occurring, plant-based omega-3 – they need it in the DPA/EHA form.

    • argylesock says:

      Did you make a small typo here? I think you mean EPA and DHA. I’ve learned since I wrote the blog post above that the omega-3 naturally found in higher plants include alpha-linolenic acid (ALA). The carbon chain in ALA is 18 carbons long, whereas EPA and DHA are 20 or 22 carbons long.

      Are you saying that human bodies (and fish bodies) can convert the 18-C fatty acid (ALA) into the longer fatty acids EPA and DHA? I’m not enough of a physiologist or biochemist to answer that question. You seem to be saying that it can happen, but that it’s inefficient.

      I’m thinking that people can, and many do, survive without eating fish oil. In that sense oilseed Omega Camelina doesn’t seem to be the only possibility. Which doesn’t mean that I’m dissing this particular GM crop!

      I want to look more into how its development is being funded, esp whether any biotech giant (Monsanto, BASF etc) has got involved yet. I’m concerned that in Europe including Britain, oilseed Omega Camelina could face the same legal and political challenges that overcame potato Amflora. Whether or not it offers a sensible way forward scientifically, a GM crop needs to jump through legal and political hoops.

      None of this considers the possibility of algaculture. I think algaculture could be a complementary response, even a rival response to oilseed Omega Camelina.

      • Yes – typos, sorry:) And yes humans and some fish can convert ALA but some fish, and particularly I think it is marine rather than freshwater fish, can’t. So, yes, we can make do with our (inefficient) conversion process, but the marine fish don’t have that option: they need the EPA/DHA. Whether we “need” to eat those fish is a whole other question…

        I recently took a genomics course as I felt things had moved on so far and so fast since I was a student 10 years ago. And I was amazed just how far and just how fast things had gone. No matter what anyone of thinks of GM, it (in its many and varied guises) is here to stay. It’s probably here in many more ways than we can even begin to conceive . It may well be a case of sowing the wind and reaping a whirlwind – only time will tell (or it won’t tell, because how will we ever know if some genetic typo was human-engineered or “natural”). But, to mix metaphors some more, I think the GM horse bolted from the stable many years ago.

  3. Pingback: Feeding vegetable oils to farmed salmon | Science on the Land

  4. Pingback: Paterson’s curse: rival for a GM crop? | Science on the Land

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