DNA Barcodes For Food Find Hidden Ingredients, Fake Medications

Scientists have discovered a range of new uses for a Canadian technology that can be used to peer into 30,000-year-old permafrost, detect phoney herbal medicines and catch invasive species before they sneak across borders.

Researchers from around the world are "fingerprinting" most of the planet's species by taking samples of their DNA and cataloguing them in a comprehensive reference library.

The DNA creates a so-called barcode that can identify real ingredients in food, quickly analyze water quality and reveal how the environment has changed over millenia.

Bob Hanner, a professor at the University of Guelph where the technique was developed, said barcoding gives governments, businesses and people a reliable way of knowing what they're eating, importing and buying.

"We have a very powerful tool to identify species in processed products that you wouldn't normally be able to identify using traditional morphological techniques," Hanner said from Guelph, Ont., before heading to an international conference on barcoding in Australia starting Monday.

"It's a very exciting time."

Researchers from dozens of institutions are steadily building the library of barcodes by taking short gene sequences from samples of birds, fish, mammals, insects and other life forms at herbaria, museums and other facilities.

They hope it will one day give them a master list of the world's species that can be used by corporate interests and government agencies for a growing number of applications.

Since being developed at Guelph in 2003, the technique has been adopted by the U.S. Food and Drug Administration as a regulatory tool and was used to identify mislabelled cheap fish being sold at American restaurants as more expensive species.

The Canadian Food Inspection Agency is using barcodes to collaborate with its U.S. counterparts to identify seafood, pest insects and pathogenic fungi. Environment Canada is also using it to measure species diversity in watersheds and identify materials they've confiscated, Hanner said.

But Hanner says that as the library grows, so do the ways they can use barcoding.

Scientists in Malaysia who are contributing to the plant barcode library used it to reveal that a herbal medicine didn't contain the ingredient it promised would treat malaria and diabetes. Others found weeds in herbal teas.

A team also discovered the presence of a rare woolly rhino, bison and moose from a sediment sample taken from Siberian permafrost dating back 15,000 to 30,000 years.

David Schindel of the Consortium for the Barcode of Life at the Smithsonian Institute said such permafrost samples let them look at how the environment and species have changed over centuries.

"We'd be taking time slices up through the stratographic column to progressively younger times until we get to the present," he said from Washington, D.C.

"So we'll ask, 'What happened to those species we saw at the bottom of the sequence? Where are they now? How have they shifted?' And all those are indicators of climatic change."

Schindel said border agencies will be able to use a special quarantine barcode library to quickly detect agricultural pests, disease-carrying insects, fungi and invasive species before entering a country.

Researchers also hope that it might also answer one of science's most elusive questions.

"I see this as addressing one of the grand challenges of biological science, which is to answer the question, 'How many species are on the planet?'" Hanner said.

"That's a fundamental big science question that no one's been able to answer."

In 2005, there were 33,000 records covering 12,700 species in the Barcode of Life Data Systems at the University of Guelph. Now there are almost 1.4 million records banked, representing roughly 167,000 known and provisional species.

The scientists believe barcoding could become a standard way of doing business as discerning consumers and governments demand their goods are deemed to be genuine.

"It's going to become increasingly important to keep international markets open, to have countries being able to authenticate their products," Schindel said.

"Otherwise, they're simply not going to be able to get them in."