Barcoding Bushmeat

I’m beginning to think that my LWON byline should read: Virginia Hughes, the one who writes about obscure applications of DNA testing. First there was the story about the scientist who found a rare DNA blip that could prove that the corpse in Napoleon’s tomb really is Napoleon. Then there was the team that screened DNA from a mouse’s tail to solve an international insurance dispute. And now I’ve learned that DNA tests could help save two wood grouse species from extinction.

The wood grouse, or capercaillie, is a 12-pound bird that was once found all over Europe and Asia. People have hunted them since the Middle Ages, for fun and and for food. Apparently, capercaillies are the tastiest game birds in Europe, with delicate meat that’s “whiter than pheasant“*.

Partly because of hunting, capercaillie numbers have plummeted in the past couple of decades. For example, at last count there were just 627 Cantabrian capercaillie, a species found in northern Spain, down 70 percent since 1981.

Hunting capercaillies is now illegal in Spain and in most other places in Europe**, but catching poachers and meat traders is hard. Once a bird has been de-feathered, butchered, processed, and thrown into a huge container ship, say, how can law enforcement really tell between capercaillie, quail, partridge or pheasant?

Of course, of course, the answer lies in DNA, as I learned from a study published this month in Forensic Science International. Researchers in Madrid figured out a way to rapidly detect capercaillie DNA in meat and meat mixtures.

Their method is based on a new technology called ‘real-time PCR’ (polymerase chain reaction). They identified a tiny fragment of a gene that has the same ‘code’ in all capercaillie species, but a different code in related birds, like partridges and pheasant. The real-time PCR machine takes a meat sample and scans it for that specific piece of DNA. When it finds that special piece, the machine copies it many times over, each time tagging it with a green fluorescent dye. Eventually, enough copies are made that the machine can ‘see’ the green glow.

Older PCR techniques (which require an extra step in the lab before the target DNA can be spotted) have helped researchers identify so-called ‘DNA barcodes’ for lots of other endangered wildlife species, such as the great white shark, Chinese alligators, and Old World monkeys. In fact, barcodes for more than 97,000 species are listed on a large and freely accessible online database, called Barcode of Life Data Systems. With any luck, this resource will help curb the booming global bushmeat market, estimated at $15 billion.

*In 2001, conservationists reportedly harassed Margaret Fairlie, the elderly author of Traditional Scottish Cookery, because the book contains a recipe for capercaillie with cranberry sauce.

**Manuel Fraga Iribarne, a well-known Spanish politician, loves to hunt capercaillie — so much that after Spain’s hunting ban went into effect, he traveled to Romania to do it. (I haven’t been able to substantiate this claim, which I found here, but it’s a good story anyway.)

I stole the title of this post from a 2010 study published in Conservation Genetics.

Photo by brockvicky, via Flickr

This post was originally published on The Last Word on Nothing