GM research produces plant containing omega-3 fish oils

The Guardian reports, 8th July 2015: Fish oil grown on the farm has come a step closer following promising results from a genetically modified crop trial.

British scientists have developed a GM oilseed plant, Camelina sativa or “false flax”, whose seeds contain omega-3 fatty acids normally only present in oily fish such as salmon, mackerel and herring.

The first GM oilseed crop harvest at Rothamsted Research that could produce fish oil.  Photograph: Rothamsted Research/PA

The first GM oilseed crop harvest at Rothamsted Research that could produce fish oil.
Photograph: Rothamsted Research/PA

The new study conducted at Rothamsted Research in Harpenden, Hertfordshire, showed that the plants were able to synthesise useful amounts of fish oil in field conditions without affecting their yield.

Oils could provide feed for farmed fish and ultimately be used as a health supplement in human foods such as margarine

The next stage of the research will involve testing different strains of the crop and comparing them with conventional Camelina.

It is primarily aimed at finding a plant-based sustainable food source for farmed fish. But plant-produced fish oil may also find its way into supplements and fortified foods such as margarine.

Rothamsted scientist Dr Olga Sayanova said: “We are delighted with the results of our first-year field trial. “Finding a land-based source of feedstocks containing omega-3 fish oils has long been an urgent priority for truly sustainable aquaculture. Our results give hope that oilseed crops grown on land can contribute to improving the sustainability of the fish farming industry and the marine environment in the future.”

Omega-3 oils are important to fish farming because fish need them to stay healthy but do not naturally produce the substances themselves. They are manufactured by marine algae which are eaten by small fish and passed up the food chain.

Farmed fish consume huge quantities of fish oils either directly or in fish meal. In 2011 around 80% of all the fish oil produced in the world went to fish farms. Experts believe the sector is growing so fast, conventional sources of fish oil will in future not be sufficient to meet the demand.

The UK aquaculture industry alone is worth €3.2bn (£2.3bn) and accounts for a quarter of all EU production of fish, molluscs and crustaceans.

Fish oils — specifically the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — are known to protect against heart disease and may have other health benefits such as combating inflammation and promoting better brain function.

Although some plants, such as flax, produce omega-3 oils they are of a different “short-chain” strain that do not have the same properties.

The Rothamsted scientists have manufactured synthetic genes based on those found in marine algae that are involved in the production of long-chain omega-3 fatty acids. By inserting the genes into Camelina plants, they produced a crop capable of generating fish oils in its seeds.

Only the seeds contain EPA and DHA – other parts of the plant including the stem and leaves are unaffected.

Three varieties of plants have been grown, one implanted with four synthetic genes, another with five and the third with seven.

Camelina sativa, a cousin of oilseed rape, has a long history of being grown for its seed oil, which was used to light lamps until the 18th century. Like common flax, or linseed, its seeds are naturally rich in the plant version of short-chain omega-3 fatty acids.

The research is reported in the journal Metabolic Engineering Communications.

Source: The Guardian, 8th July 2015. For the full text, see www.theguardian.com/environment/2015/jul/08/farm-grown-fish-oil-a-step-closer-following-gm-crop-trial

 

Marinet observes: We provide a copy of this article on our website.

This GM development poses a number of questions, many of which need careful thought and further research.

The development (GM adapted plant producing omega-3 fish oils) appears, at first glance, to take the pressure off the relentless fishing of wild stocks of fish in order to feed farmed fish, such as salmon. Wild salmon, herring and mackerel are (due to their foraging) accumulators of omega-3 fish oils. They obtain these by eating algae which contain these oils. Therefore if farmed salmon can be fed a GM plant which contains these oils instead of relying on the harvesting of wild fish to supply these oils, a pressure appears to have been taken off the oceans.

However salmon are carnivores, and wild salmon eat other fish in addition to eating algae as an essential element of their overall diet. Thus the need for fish protein by farmed salmon is not likely to be reduced by this development. All it will ensure is that farmed salmon are fed omega-3 fish oils which, because they are absorbed by salmon into their bodies, will thus be available to humans when they eat the farmed salmon. The farmed salmon will therefore be “healthier” in this regard, both in their own terms and for human consumption.

So, farmed salmon will be “healthier”, but the pressure to feed farmed salmon with wild-harvested fish (protein) during the farmed salmon’s rearing is unlikely to diminish.

Another factor which also remains true is that fish farming is a version of “intensive farming” — a large number of animals crowded together during their life in a very confined space. This gives rise to disease, and even though farmed salmon may be fed with a GM substitute for omega-3 fish oils, their “well-being” will continue to rely upon an intensive regime of pharmaceuticals in order to ensure that they stay alive. This life-long dependency on pharmaceuticals makes their value as food to humans limited — the pharmaceuticals have “residence” in the salmon’s body and so are present when eaten by humans, thus leading to advice from the UK Government not eat too much farmed salmon. Further, the persistence of a human designed mariculture (farming of marine life) means that considerable pollution (in the form of faeces, parasites, and chemicals) is placed on the areas of inland sea where this mariculture takes place.

GM sourced omega-3 fish oils will not eliminate this pollution. Indeed, if it encourages an expansion of fish farming, it will intensify this adverse consequence.

The “success” reported in the article is also limited in another regard. Whilst the researchers may have developed versions of Camelina sativa (also known botanically as “false flax”) — one version has 3 inserted synthetic genes, another version has 5 inserted synthetic genes, and a further version has 7 inserted synthetic genes — all of which appear to be stable when grown in field conditions (i.e. the field versions of the plant produces the same level of omega-3 fish oils as the laboratory/greenhouse versions), this does not mean that the plant is safe to use.

For example, whilst Camelina sativa is largely self-pollinating (90% of fertilisation is by this means), it still has to be shown that these genetically altered plants do not pose a risk of cross-pollination with other plants, especially near varieties and similar species. If this were to be so, this “success” would turn to nought.

Equally important, it still requires to be shown that eating, both by farmed fish and humans, of these GM omega-3 oils is safe. The insertion of genes into a new host is an uncertain business. It may produce the desired effect that is being sought, but the new gene sequence in the host species (in this instance, Camelina sativa) may also cause the plant to produce other new proteins which it did not produce before. The production of such proteins is wholly unpredictable. Some of these new proteins will be wholly benign — pose no health risk when eaten — but other new proteins may be poisonous and produce serious adverse consequences. Furthermore, some people may be sensitive to these new “adverse” proteins, whereas other people may not. So, there is no clear-cut rule.

The occurrence of new proteins that are adverse to animal and human health require an enormous amount of research and testing before the true measure of safety can be established, and one of the serious problems that GM foods have faced to date is exactly this issue. How do we determine that the new proteins are “safe”? At present, the science is tending to run on a “suck it and see” basis, with the human population being used as the “guinea pig” — a let’s give it a go approach, and provided no adverse health effects emerge then everything is okay . . . . In short, a huge open experiment.

Can we afford to do this with GM omega-3 fish oils, feeding them not just to farmed fish but also permitting the “fortifying” of human foods such as margarine with these GM manufactured oils?

The advocates and supporters of GM often accuse the opponents of GM as being techno-phobes. However when there is a perceived risk, and the present level of scientific knowledge regarding that risk is limited and uncertain, then the “precautionary principle” applies. The precautionary principle — no licence until safety exists in a proof-positive form — is a legal principle, and not just a “cry wolf” assertion. It exists because experience has taught us of its necessity.

GM omega-3 fish oils still have to pass this test.


Please do share this

  • Facebook
  • Twitter
  • Delicious
  • StumbleUpon
  • Add to favorites
  • email hidden; JavaScript is required
  • RSS