[tt] Fish Tale Has DNA Hook - Students Find Bad Labels - NYTimes.com

[Brian Atkins]

http://www.nytimes.com/2008/08/22/science/22fish.html?_r=1&oref=slogin&pagewanted=print

Many New York sushi restaurants and seafood markets are playing a game of bait 
and switch, say two high school students turned high-tech sleuths.

In a tale of teenagers, sushi and science, Kate Stoeckle and Louisa Strauss, who 
graduated this year from the Trinity School in Manhattan, took on a freelance 
science project in which they checked 60 samples of seafood using a simplified 
genetic fingerprinting technique to see whether the fish New Yorkers buy is what 
they think they are getting.

They found that one-fourth of the fish samples with identifiable DNA were 
mislabeled. A piece of sushi sold as the luxury treat white tuna turned out to 
be Mozambique tilapia, a much cheaper fish that is often raised by farming. Roe 
supposedly from flying fish was actually from smelt. Seven of nine samples that 
were called red snapper were mislabeled, and they turned out to be anything from 
Atlantic cod to Acadian redfish, an endangered species.

What may be most impressive about the experiment is the ease with which the 
students accomplished it. Although the testing technique is at the forefront of 
research, the fact that anyone can take advantage of it by sending samples off 
to a laboratory meant the kind of investigative tools once restricted to Ph.D.’s 
and crime labs can move into the hands of curious diners and amateur scientists 
everywhere.

The project began, appropriately, over dinner about a year ago. Ms. Stoeckle’s 
father, Mark, is a scientist and early proponent of the use of DNA bar coding, a 
technique that greatly simplifies the process of identifying species. Instead of 
sequencing the entire genome, bar coders — who have been developing their field 
only since 2003 — examine a single gene. Dr. Stoeckle’s specialty is birds, and 
he admits that he tends to talk shop at the dinner table.

One evening at a sushi restaurant, Ms. Stoeckle recalled asking her father, 
“Could you bar code sushi?”

Dr. Stoeckle replied, “Yeah, I think you could — and if you did that, I think 
you’d be the first ones.”

Ms. Stoeckle, who is now 19, was intrigued. She enlisted Ms. Strauss, who is now 18.

Their field technique was simple, Ms. Stoeckle said. “We ate a lot of sushi.”

Or, as Dr. Stoeckle put it, “It involved shopping and eating, in which they were 
already fluent.”

They hit 4 restaurants and 10 grocery stores in Manhattan. Once the samples were 
home, whether in doggie bags or shopping bags, they cut away a small piece and 
preserved it in alcohol. They sent those off to the University of Guelph in 
Ontario, where the Barcode of Life Database project began. A graduate student 
there, Eugene Wong, works on the Fish Barcode of Life (dubbed, inevitably, 
Fish-BOL) and agreed to do the genetic analysis. He compared the teenagers’ 
samples with the global library of 30,562 bar codes representing nearly 5,500 
fish species. (Commercial labs will also perform the analysis for a fee.)

Three hundred dollars’ worth of meals later, the young researchers had their 
data back from Guelph: 2 of the 4 restaurants and 6 of the 10 grocery stores had 
sold mislabeled fish.

Dr. Stoeckle said he was excited to see a technology used in a new way. “The 
smaller and cheaper you make something,” he said, “the more uses it has.” He 
compared bar coding to another high-tech wonder turned everyday gadget, GPS.

Eventually, he predicted, the process will become more automatic, cheaper and 
smaller so that a handheld device could perform a quick analysis and connect to 
the database remotely. What his daughter did, he said, is like dropping film off 
at the supermarket for developing. The next generation could be more like a 
digital camera that displays the results on the spot.

The results of Ms. Strauss and Ms. Stoeckle’s research are being published in 
Pacific Fishing magazine, a publication for commercial fishermen. The sample 
size is too small to serve as an indictment of all New York fishmongers and 
restaurateurs, but the results are unlikely to be a mere statistical fluke.

The experiment does serve as a general caveat emptor for fish lovers, 
particularly because the students, their parents and their academic mentor all 
declined to give the names of the vendors, citing fear of lawsuits. Besides, 
they noted, mislabeling could occur at any stage of the process.

Dr. Stoeckle was willing to divulge the name of one fish market whose products 
were accurately labeled in the test: Leonards’ Seafood and Prime Meats on Third 
Avenue. John Leonard, the owner, said he was not surprised to find that his 
products passed the bar code test. “We go down and pick the fish out ourselves,” 
he said. “We know what we’re doing.” As for the technology, Mr. Leonard said, 
“it’s good for the public,” since “it would probably keep restaurateurs and 
owners of markets more on their toes.”

Ms. Stoeckle said the underlying message of the research was simple: “If you’re 
paying for white tuna and you’re eating tilapia, I think you’d want to know that.”

Although the students did not present the project for a grade at school, they 
made sure to mention it on their college applications. Both will enroll at Johns 
Hopkins University this fall.

Neither, however, expects to major in the sciences. “I’ve always been into art 
history,” Ms. Strauss said, “which is really different from this.” Ms. Stoeckle, 
who is the granddaughter of the entertainer and arts patron Kitty Carlisle Hart, 
is thinking about studying writing or psychology. But that, they said, is the 
point. “If we found it interesting — which we did — I think lots of people like 
us can do it, too,” Ms. Stoeckle said.

Peter B. Marko, a professor at Clemson University who used a more detailed 
genetic technique in a 2004 paper to show that red snapper was commonly 
mislabeled, called their project “quite remarkable,” though he added that 
genetic analysis had been simplified to the point that high school students 
could now perform the task without sending samples off.

Mr. Marko prefers to work with whole genomes — “more information is better,” he 
explained — which can be sequenced now with lightning speed. He plans to perform 
a broad genetic comparison of fishes that were separated millions of years ago 
by the rise of the Isthmus of Panama. “The technology is allowing us to ask 
questions that really would not have been possible in the past.”

The students worked under the tutelage of Jesse H. Ausubel of Rockefeller 
University, a champion of the DNA bar coding technique. As for Ms. Strauss and 
Ms. Stoeckle, Dr. Ausubel said they “have contributed to global science” by 
adding to the database, built on a model similar to that of Wikipedia, in which 
people around the world can contribute.

In a way, Dr. Ausubel said, their experiment is a return to an earlier era of 
scientific inquiry. “Three hundred years ago, science was less 
professionalized,” he said, and contributions were made by interested amateurs. 
“Perhaps the wheel is turning again where more people can participate.”

-- 
Brian Atkins
Singularity Institute for Artificial Intelligence
http://www.singinst.org/