AquAdvantage Salmon, The Only Genetically Modified Fish On The Market

The AquAdvantage salmon grows twice as fast as its wild counterpart, and is already being sold commercially. But are these fish as unethical and dangerous as some would suggest, or a useful tool to fight food insecurity and environmental challenges?

In 1989, American company AquaBounty Technologies begun developing a new genetically engineered breed of Atlantic salmon that could grow twice as fast as an Atlantic salmon in the wild.¹ And while the AquAdvantage salmon was still a long way from being approved for commercial production or sales, the potential of genetically modified (GM) animal products on our supermarket shelves quickly went from hypothetical to a viable reality.¹ 

In 2015, this hypothetical became a reality. After years of discussion, the U.S. Food and Drug Administration (FDA) approved AquAdvantage salmon to become the world’s first genetically modified animal approved for commercial production and consumption.² Now, with fresh discussions around new genetic techniques back on the EU agenda, the decade long story of the AquaAdvantage salmon could offer us a looking glass into the future and challenges of GMOs.

Why GMOs?

Over the past decade, Atlantic salmon populations have reached an all time low. In 2020, Atlantic salmon catches amounted to 915 tonnes, marking a decline of 19% and 29% compared to the average catches of the preceding five and ten years, respectively.³ But even before the AquAdvantage salmon was approved to be commercialised, populations were in a steep decline with no clear signs of improving.^4,5 Salmon farming quickly emerged as a viable solution to meet the demand of waning wild capture fisheries, and today, around 70% of global salmon production comes from aquaculture, with the majority of production ending up in higher income countries. The industry has grown so much, that farmed salmon alone represented over 16% of the entire aquaculture export industry’s value in 2019.⁶

But over the past decades it’s become clear that salmon farming presents several concerns of its own - like pollution flowing into nearby waterways, the impacts of antibiotic use, and unsustainable reliance on wild fish as a key component of feed. There’s also the issue of selectively bred farmed salmon escaping into the wild, where they can cause damage to the already struggling wild populations by competing for the same food, spreading pathogens and parasites, and weakening the genetics of wild salmon through interbreeding.^7,17 

In August 2023, Iceland faced one of its largest escapes in recent years when thousands of farmed salmon escaped from a pen in Patreksfjörður. With estimates from the Norwegian Marine Research Institute suggesting that the average number of yearly escaped salmon from Icelandic farms is almost double the total wild population, escapes have raised serious environmental concerns.

AquaBounty Technologies emerged with the AquAdvantage salmon as a proposed solution to these concerns - stating that their new look salmon is antibiotic free, sterile, and requires 25% less feed than regular farm raised salmon to reach market size.⁸ On top of this, they were also engineered to grow twice as fast as the regular salmon, reaching market size in significantly less time - offering a win for producers too.¹ To achieve this, AquaBounty modify their salmon by removing the typical growth-hormone regulating gene in the Atlantic salmon, and replacing it with the growth hormone regulating gene from the faster-growing Chinook salmon and a promoter sequence from another fish, the ocean pout. This sequence is like a genetic "on-switch" that regulates when and where in the body the growth-hormone regulating gene is expressed. Combined, these modifications allow the salmon to grow year-round instead of only during summer and spring, when regular Atlantic salmon see greater growth.¹

While the proponents argue GMOs like the AquaAdvantage salmon offer a number of benefits, debates persist over ethical, socio-economic, and environmental concerns that come with unnaturally meddling with the DNA of plants and animals.⁹

Aquabounty AquAdvantage salmon can reach adult size in 16 to 18 months instead of 36 months for regular Atlantic salmon. These transgenic salmon eat 25 per cent less feed and are about 20 per cent more efficient at converting that food to flesh. 

The criticisms

Before the AquAdvantage salmon had even been accepted by the FDA for commercialisation, environmental advocacy groups, consumer rights organisations, animal welfare activists, and segments of the scientific community were quick to offer their critique. Terms like “Frankenfish” found their way into the headlines and it became clear that opinions were split on the new super-salmon.¹⁰ While the list of critiques by anti-groups is long, they were broadly centred around a few key concerns.

1. Lack of transparency

Some of the criticisms of AquAdvantage salmon were related to the approval process and a lack of transparency surrounding the labelling of genetically modified foods for consumers. The U.S. FDA regulates genetically engineered foods through a process that prohibits the agency from disclosing information obtained during review to the public. This lack of transparency raised concerns about how much public oversight and input was acknowledged in the approval.¹¹ 

Labelling requirements also raised concerns. Initially, the FDA did not require labelling for the genetically modified salmon, stating that it was similar to the wild variety. However, consumer advocacy groups have argued that the consumers have the right to know if their food has been genetically modified, leading to the National Bioengineered Food Disclosure Act, which mandates labelling for GMOs, including AquAdvantage salmon. Despite this, exemptions for restaurants and some retail settings limit consumer access to information about the presence of genetically modified salmon in their food, highlighting ongoing challenges in ensuring transparency in the food supply chain.¹¹

2. Health concerns

Genetically modifying any organism may introduce new proteins or allergens into the food that were not present in the original organism. While these additions can be harmless, they can also trigger allergic reactions in sensitive individuals that were not previously sensitive to the original unaltered product. This common and well-founded food safety concern also applies to AquAdvantage salmon.¹² 

Over the past decades, major medical groups have presented research and released statements highlighting that there is actually no evidence that a modified product presents any unique safety risk to human health compared to conventionally bred products.¹¹ However, it has also been clearly emphasised that different GMOs have different inserted genes, and as a result, their potential impact to human health should be evaluated on a case-by-case basis before they become available in the public market.¹³ Regarding the specific case of the AquAdvantage salmon, the FDA and the Canadian Science Advisory Secretariat concluded that AquAdvantage salmon does not present any additional risk to human health compared to wild salmon.^2,14

3. Environmental issues

In 2004, transgenic salmon was shown to present a potential threat to wild populations under certain conditions if it escaped to the surrounding environment, with the researchers requesting for this to be taken into special consideration.^15,16 Considering over one million domesticated salmon were reported to have escaped Scottish farms alone, between 2002 and 2006, escaped fish from net pens into the wild remains a valid concern to this day.¹⁷

However, there are ways to navigate this risk. For example, environmental harm appears to decrease significantly when the fish are raised in contained land-based farms, with an additional biological containment, like by breeding only one sex, or sterilising the transgenic fish so they aren’t able to breed with wild populations if they were to escape.¹⁷ According to AquaBounty technologies, to comply with the FDA’s requirements on this matter, their salmon are all sterile females raised in well contained inland facilities.⁸ The FDA and the Fisheries and the Canadian Science Advisory Secretariat concluded that these measures significantly reduce the risk of the AquAdvantage salmon’s environmental impact to ‘extremely low’.^{2, 14}

Learn more about the impacts of salmon hatcheries on wild populations

But this didn’t seem to appease the concerns of some, and in 2020 a federal judge in San Francisco ruled that the FDA needed to better investigate the potential environmental effects of the AquAdvantage salmon were it to escape to the wild.¹⁹ After further investigation, the FDA maintained that, given the low likelihood of the salmon escaping and interbreeding with wild Atlantic salmon, their potential impact on the environment is in fact ‘extremely low’.²

There are also some indications that domesticated transgenic fish do not fare well in the wild, however researchers call for more research on the matter to better understand the potential impact of transgenic fish in the wild.²⁰

A view of AquaBounty Technologies inland farm in northeast Indiana. The farm is capable of raising 1,200 metric tons of salmon each year. Photo courtesy of AquaBounty.

What is the future of genetically engineered fish?

So far, the AquAdvantage salmon is still the only commercially available GMO fish worldwide for human consumption. It is also only being sold in the USA and Canada - with no other international governments, including the EU, showing any clear will to seriously consider GM salmon production or sales within their own borders.

The unsolved debates around ethics and responsibility also persist. While GMOs are seen by some as an unethical and irresponsible way to solve some of today’s problems, several organisations and researchers have recognised it as a potentially useful new tool to address issues like overfishing, food security, food safety, and resource use. Professor Andreas Boecker, who studies consumer perception of agricultural technologies at the University of Guelph, told FoodUnfolded that resistance to GMOs also often stems from “A longing for what is natural and the simpler way of living; a general distrust in the food industry; and what we have seen becoming more intense over the last 10 years, a general distrust in science.”

Read more on the current EU gene-editing debate here

However, even proponents of GM agree that it should only be used with extreme care, following strict regulations and monitoring by both scientific and regulatory entities. Professor Rex Dunham from the School of Fisheries Aquaculture and Aquatic Sciences at Auburn University, told FoodUnfolded that while it’s hard to know how long it will take, “In the future of feeding people and protecting the environment, most farmed fish will be genetically improved. And if that allows us to grow food with a smaller footprint, that’s good for society. However, we do need to choose the proper approaches responsibly. We have to be logical and well aware of the adverse and beneficial effects in all cases. Choosing the right traits and approaches is important.” Further stating that “Adopting a conservative gradual approach, integrating sterilisation and other safeguards is how we need to proceed.” 

With the current resistance to accept GMOs in many countries worldwide, it’s clear this technology still has a long way to go before it garners wider consumer trust, which according to Professor Andreas Boecker, requires a deep understanding of the current food systems we have in place. “We need to compare the effects of genetic engineering to the ones of the current food systems. And many people who are against it, compare it to an inexistent ideal world where everything is organic.” 

Whether GMO fish will ever become an integral part of food systems worldwide, only the future can tell. However, this clearly can’t happen without a dramatic shift in public perception of GMOs. This required shift underscores just how important early stakeholder engagement is if GM producers are to establish trust and transparency among all involved parties.²¹ There’s also more work needed to better understand exactly how genetically engineered animals would truly compare to their traditionally bred counterparts with respect to their impacts on society, the environment, animal welfare and ethics. Finally, we’re going to need robust monitoring and regulatory frameworks to make sure we’re consistent with our application of genetic engineering techniques to our food.