By ITAI YANAI AND MARTIN LERCHER
January 11, 2016
Imagine the perfect evening. You open the perfect vintage, sit down for dinner with your perfect spouse, and enjoy the perfect salmon. Alas, there is no perfection. Especially not in the salmon.
The fish you pull out of a river or buy at your local supermarket is an individual with many things in common with all the other salmons of the world, but its genome is unique: it contains millions of mutations that differentiate it from its brethren and sistren. In fact, each and every cell of tonight’s salmon has its own unique mutations. This follows from another lack of perfection at the level of cell division: as DNA is duplicated, errors are inevitably introduced, and since there were many billions of such divisions as the egg developed into a fish, it is now an intricate mosaic of mutations.
Could you get sick by eating a mutated salmon? Well, you’ve already tested this out. Every day of your life, actually. With every single meal, with every single bite even, you swallowed millions of cells, each with its own mutations. One more reason to have another bite, but no reason to worry. Our ancestors have eaten mutants long before we even climbed down the trees – there is no other kind of food.
At the end of 2015, the FDA approved the growing of salmon genetically engineered by the company AquaBounty – the first example of a genetically modified animal approved for food, immediately sparking controversy. These “AquAdvantage” fish take less time to grow to adulthood, thus allowing the company to produce them faster. Many supermarkets worldwide, including Wholefoods and Trader Joes, have pledged not to sell these fish. Why? Because many consumers fear that eating genetically modified animals is unhealthy. But actually, these salmon are essentially only a single mutation away from “normal” salmon. It’s highly likely that you yourself have enjoyed countless mutations in your “natural foods” that are actually variations upon the same theme as the mutations in GMO foods. The specific mutation was introduced by copying a piece of DNA from another species of fish into the salmon genome. But an identical stretch of DNA could have arisen through naturally occurring mutations – there is no fundamental difference. So, in terms of risk, this fish is as genetically modified as anything we eat.
But if this type of mutation occurs naturally, then why don’t we see wild salmon that grow as fast as the one developed by AquaBounty? The AquAdvantage fish grow faster because they never take a break – they grow the whole year round. “Normal” salmon grow only half of the year. Why? Because in winter, wild salmon don’t find enough food to grow, and if they invested the little resources they find into more meat, they’d soon starve. Thus, a hopeful salmon with a year-round-growth mutation akin to that introduced into AquAdvantage would not live long – that mutation would die out, leaving no trace after a generation or two. In contrast, growing in tanks where food is provided year-round, the genetically engineered salmon are perfectly adjusted to their artificial environment. Actually, if wild salmon would be grown for thousands of years in such a season-less environment, they’d likely evolve to the same type of year-round growth.
Some folks worry that genetically modified salmon might escape from the watertight security measures mandated by the FDA, and that the mutation would then spread through wild populations. However, what is most likely to happen if such a salmon escapes and joins its wild relatives is a complete failure. Just as with a natural mutation of the same effect, the hopeful escapee would find that year-round growth is not a good idea in a world with seasons, and the mutation would die out quickly (incidentally, the genetically modified salmon are also lousy at courtship).
What this discussion boils down to is that the issues commonly raised against GMO foods may really be symptoms of a larger problem: issues against the concept of evolution. There is no “playing God” with creation, because there was no creation in the first place. Life evolves, yet many misunderstand or deny this process. When we look at GMO foods from an evolutionary angle, we realize that the risks of harm to people or to our environment are vastly over-stated. Evolution occurs all of the time, and it is no sucker: new mutations are tried out continuously, and wild salmon are by now so well adapted to their rough environment that a competitor optimized for life in a cozy tank is no match for them. Surely, oversight is required to continue to apply common sense. But the plants and the salmon that were genetically modified for food are the same sort of variants that occur naturally; and they are subject to the same law of natural selection that has been acting around us for eons.
So enjoy your salmon – even if it’s not perfect, it certainly is healthier than that triple chocolate dessert.