Molecular genetics becomes a weapon against food fraud, illegal trafficking, and invasive species
In ports and airports around the world, as goods and passengers cross borders non-stop, a silent scientific revolution is underway. A revolution that cannot be seen, but which leaves invisible traces in every sample analyzed: those of DNA.
DNA barcoding (the technique that allows a living species to be accurately identified by reading a fragment of its genetic code) is changing the way we combat food fraud, illegal trafficking, and the spread of invasive species. From verifying tuna sold as ‘red’ to adulterated spices, protected woods and endangered animals, molecular genetics is now one of the most effective tools for defending food safety, biodiversity and commercial legality in a globalized economy (as well as being used in other fields such as art and archaeology).
TAKEAWAYS
Silent fish, false labels
“In the United States, testing imported fish using DNA barcoding, particularly for salmon, is mandatory,” explains Jessica Frigerio, a researcher at the University of Milan-Bicocca who works on these applications. “In Europe, there is no similar requirement yet, although it is a technique that is increasingly being used by control authorities.” This regulatory difference reflects different approaches to food safety, but that could soon change. In particular, great strides are being made in this field. “The intention is to work with European customs authorities, which actually use this technique on fish, as they do in America, focusing mainly on tuna,” says Frigerio. This fish is one of the seafood products most at risk of commercial fraud, with less valuable species often being sold as bluefin tuna or other high-value varieties.
“They obviously carry out random checks, as they cannot analyze every single shipment,” explains the researcher, “but they use DNA barcoding to check the species, authenticate it, and thus verify the integrity of the commercial supply chain.” This work is essential not only to protect consumers from fraud, but also to combat illegal fishing and protect endangered species.
The mechanism is relatively simple in concept, although technically sophisticated: a small piece of tissue is taken from each sample of fish seized or checked, from which DNA is extracted. The genetic sequence obtained is then compared with vast reference databases containing the “genetic signatures” of hundreds of fish species. Within a few hours, the identity of the fish is revealed with scientific certainty.
“The problem of fish fraud is very serious,” Frigerio emphasizes. “It’s not just about deceiving consumers on price, but there are also implications for public health and the conservation of marine species.” Some fish species, in fact, may contain higher levels of mercury or other contaminants, while others are protected by international conventions and their trade is prohibited or strictly regulated.
The spice wizards
While fish testing is becoming increasingly standardized, new horizons are opening up for the application of the same technique. “In the food sector, many other applications can be explored, for example with spices,” says Frigerio. “In this case, we want to try using not only classic DNA barcoding, but also DNA metabarcoding, which analyzes all the species present in a sample at the same time.”
The difference between the two techniques is substantial. While traditional DNA barcoding identifies a single dominant species in a sample, metabarcoding can reveal the entire ‘cast’ of organisms present, even in minimal traces. “This is essential for spices,” explains the researcher, “because if you have a pure spice, unless it is intentionally contaminated by another species, classic barcoding works well. But spices are often mixtures, or they are contaminated or adulterated with lower-value plant material.”
There are numerous and worrying examples of fraud in the spice sector. “Oregano, for example, is widely adulterated in this sense, highly contaminated,” reveals Frigerio. “Other similar but less expensive herbs are added, or even leaves with no commercial value that have been treated to resemble oregano.” Even pepper, one of the most traded spices in the world, is not immune to these practices. “There are obviously limits to a certain percentage of natural contamination, linked to the harvesting and processing process,” the researcher points out. “However, when these limits are exceeded, or when the contamination is clearly intentional, it becomes a real commercial scam, and it is something that the authorities are starting to work on a lot, precisely because it is economically important.”
The global spice market is worth billions of euros, and the possibility of adulterating expensive products with low-cost substitutes is a strong temptation for unscrupulous operators. DNA metabarcoding can expose these frauds with a precision that is impossible to achieve with traditional methods based on physical appearance or taste.
Laying the foundations: the database project
But to use DNA barcoding effectively, a solid infrastructure of genetic reference knowledge is needed. “We are working on a pilot project to create a database specifically for spices,” announces Frigerio, “because this is very important and still relatively lacking. Customs authorities also need reference databases that are secure and validated, with species that are first identified and certified by expert taxonomists, and then we can perform DNA analysis.”
The idea is ambitious but necessary: “We want to collaborate with European customs authorities to develop this tool,” continues the researcher. It would be a database specifically designed for customs control needs, with certified genetic sequences of all major commercial species and their most common adulterants.
“It’s a very complicated job because it requires specific and rigorous steps,” admits Frigerio. “You need plant material that has been validated by a qualified taxonomist or that comes from a certified herbarium. In any case, it must be material whose identity you are absolutely sure of. Then you have to perform DNA analysis using standardized protocols, verify the quality of the sequences, and upload them to the database with all the necessary metadata.” It is a long and meticulous process, but one that is essential to ensure the reliability of future controls.
Some European customs authorities, however, have made a significant investment in this direction, purchasing fairly expensive advanced biomolecular instruments to perform real-time analyses independently. These are a few virtuous examples that show how public authorities are focusing on advanced technology to modernize controls.
Airports: the mobile border
While ports are the main point of entry for commercial goods, airports are the frontier where all kinds of traffic converge: from food products brought in by travelers to smuggled protected species. “For airports, we are thinking of faster devices, what we call ‘ready-to-use’,” explains Frigerio. “In my opinion, they are more feasible in contexts such as large international hubs, where a quick response is needed.”
The idea is to develop diagnostic kits that can be used directly in the field, without the need to send samples to specialized laboratories. “These are tools that give you a preliminary indication, an idea of what you are analyzing,” explains the researcher. “In the sense that, being ‘targeted’ analyses, i.e., designed for a particular species – which may be an invasive species, a contaminant, or a protected species – they do not completely replace laboratory analysis, but they give a quick result that allows you to decide whether or not to investigate further.”
The concept is similar to that of the rapid COVID-19 tests that have become familiar during the pandemic: a quick result that allows immediate decisions to be made, with the possibility of subsequent confirmation through more in-depth analysis. “However, confirmation from an official laboratory is always required for legal action or seizures,” Frigerio points out. “But getting an answer in two hours instead of two days can make a big operational difference.”
From the laboratory to the field: the challenge of commercialization
These rapid kits already exist at the research level. “We make them, we develop them in our laboratories,” confirms Frigerio. “But we need to find a commercial partner who is genuinely interested in serious industrial scalability, in order to market them on a large scale.” The transition from research to industrial production is always a critical moment, requiring significant investment and partnerships between academia and industry.
“That would be the next step if there were an interested buyer, a company or public body willing to invest in commercial development,” continues the researcher. The ideal model would be to identify a specific application with a defined market and develop the kit in collaboration with end users.
The possibilities for applying rapid kits go far beyond food control. “Invasive species are a huge problem, both for natural ecosystems and for the urban environment,” notes Frigerio. “We could design these kits for something that is of specific interest to phytosanitary or environmental authorities. The important thing is to meet a real, concrete need.”
The proposed working method is pragmatic: “You can start with the official list of invasive species in the European Union, focus on one of them, study it thoroughly at the genetic level, develop a specific kit and then, if it works, scale the method to other species,” explains the researcher. “But each time you have to do specific fine-tuning; there is no universal kit that works for everything.”
Tiger mosquitoes, nutria, Asian hornets, red palm weevils: these are just a few examples of invasive species that cause enormous damage in Europe. “Having rapid kits to identify them in the early stages of an infestation could allow for timely eradication measures before the problem becomes unmanageable,” Frigerio points out.
“And it could make sense, in fact, in an airport context,” the researcher continues. “Imagine intercepting a suspicious shipment or luggage containing undeclared un l plant or animal material. In two hours, you have a result that tells you whether it is an invasive or protected species. You can make immediate decisions instead of having to wait days for laboratory analysis.”
CITES and protected woods: when DNA saves species
Another crucial field of application concerns species protected by the CITES (Convention on International Trade in Endangered Species). “After food, I think CITES, i.e., the control of protected species, is the most important thing to control,” says Frigerio with conviction.
The illegal trade in endangered species is a billion-dollar business that fuels poaching and threatens the survival of countless animal and plant species. Turtles, exotic parrots, rare orchids, sturgeon caviar, ivory: the list is tragically long. “DNA barcoding can identify with certainty whether a product comes from a protected species, even when it has been processed or transformed to make it unrecognizable,” explains the researcher.
A particular case concerns precious woods. “There are protected tropical woods that are traded illegally, passed off as similar but unprotected species,” says Frigerio. “Processed wood can be very difficult to identify morphologically, but DNA does not lie.” Mahogany, rosewood, ebony: woods that are worth fortunes and for which entire forests are illegally destroyed. DNA barcoding offers customs authorities a tool to distinguish legal trade from illegal trade.
The spread of DNA barcoding in customs controls represents much more than a simple technological advance. It is a paradigm shift in the way we deal with globalization and its risks. “Before, a lot depended on the inspector’s experience, on their ability to visually recognize a species or product,” notes Frigerio. “Now we have an objective, scientific tool that can also be used by operators with less specific experience, following standardized protocols.”
This does not mean that human experience becomes superfluous. “The expert inspector remains essential for deciding what to check, recognizing suspicious situations, and interpreting the context,” the researcher points out. “DNA barcoding is a tool in their hands, not a substitute for their judgment.”
The technology is also becoming increasingly accessible. The costs of sequencers are falling, protocols are being simplified, and databases are expanding. “What five years ago required a well-equipped university laboratory can now be done in a container equipped in a port,” notes Frigerio. “And in five years’ time, we will probably have portable devices that are even easier to use.”
Despite progress, significant challenges remain. The first concerns reference databases. “There is no point in having a genetic sequence if you have nothing to compare it with,” Frigerio points out. “This is why the work of building comprehensive and reliable databases is so important.” Many species, especially in tropical countries where biodiversity is greater, do not yet have a “genetic identity card” in international databases.
The second challenge is standardization. “We need internationally shared protocols because goods cross borders,” explains the researcher. “An analysis carried out in one European country must be recognized and used in another.” The European Union is working in this direction, and some important steps forward have recently been taken, but not for all foods and cases.
The third challenge is training. “We need trained operators who are able to use these technologies correctly,” notes Frigerio. “It is not enough to buy a tool; you have to know how to use it, interpret the results, and understand the limitations of the technique.”
Towards a global DNA barcoding ecosystem
Looking ahead, the prospects are promising. “I imagine a future in which every major port and airport will have the capacity to perform DNA barcoding analysis in real time,” predicts Frigerio. “It will no longer be the exception but the norm, part of routine checks.”
The technology will continue to evolve, becoming faster, cheaper, and easier to use. “Portable devices will improve, databases will expand, and artificial intelligence will help in interpreting the results,” the researcher continues. “But the basic principle will remain the same: using the genetic code as a tool of truth, as a guardian against fraud and illegality.”
And the impact will go far beyond customs controls. “Every time we stop food fraud, we protect consumer health,” reflects Frigerio. “Every time we intercept a protected species being trafficked, we contribute to the conservation of biodiversity. Every time we identify an invasive species before it spreads, we protect our ecosystems.” DNA barcoding, invisible to most, is becoming a silent but effective guardian of legality and sustainability in global trade.
“It’s fascinating to think,” concludes the researcher, “that a microscopic molecule, DNA, can have such a big impact on society. But that’s exactly the power of science: taking something fundamental in nature and turning it into a tool for the common good.” In Europe’s ports and airports, this molecular revolution is already underway, one test tube at a time.
This series dedicated to DNA barcoding stems from the experience gained in the laboratories of the University of Milan Bicocca and the National Biodiversity Future Center thanks to the FRONTIERS program.
