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DNA extractable from fingerprints

By CHARLES CHOI, UPI Science News

NEW YORK, July 31 (UPI) -- Even if the only evidence forensic analysts can pull from a crime scene is a fingerprint smudged beyond recognition, a new technique developed by Canadian scientists soon could harvest enough DNA from the print to produce a genetic identity.

The novel system can extract DNA in only 15 minutes, even if a print has been stored for a year. Scientists expect the invention to help crime-fighters solve mysteries, and already are in talks with the Royal Canadian Mounted Police. In addition, researchers predict the technology could be at least twice as cheap as existing DNA collection methods.

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"If you wanted to use blood as a source of DNA, you have fear of contamination, people who don't want to give it, storage issues, and you have to sign a lot of paperwork to get it," research scientist Maria Viaznikova of the Ottawa University Heart Institute in Canada told United Press International. "We can now have DNA reliably and simply with our method."

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Viaznikova said her team's method consistently yields 10 billionths of a gram of DNA, on average, from a single fingerprint. The findings were revealed at the American Society for Microbiology's nanotechnology conference in New York earlier this month. Although 10 "nanograms" might not sound like much, for DNA analysis, even 0.1 nanogram is enough, Viaznikova said. "Scientists try not to use less than 5 to 10 nanograms, so this is fine."

She said forensic scientists have known for about five years that fingerprints contain DNA. However, commonly used extraction techniques need several hours or even days of lab work. "We can do it in 15 minutes," she added.

The new extraction technique is under patent. When compared with existing methods, "it is at least as twice less expensive, maybe more," Viaznikova said.

The most immediate application such a technique could find is with forensics, said molecular biologist Margaret Wallace of John Jay College in New York and one-time DNA analyst for the city's chief medical examiner's office.

"It could save a lot of time, particularly given we have this huge backlog on DNA that needs to be analyzed," Wallace told UPI. "There are hundreds of thousands of samples that need to be looked at now."

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Wallace still wants to know how well the process works on fingerprints gleaned from a variety of surfaces and kept in a variety of temperature and humidity conditions. "It's also possible that some people leave more DNA in their prints than others," she said.

Because the method is so simple and cheap, with far less overhead required than needle-based DNA sampling, experts say this could help make DNA gathering a commonplace activity -- thereby also raising privacy issues.

"DNA is unique, extremely revealing about you and your family members," privacy specialist Jay Stanley of the American Civil Liberties Union in Washington, D.C., told UPI. "This advance really highlights the need for laws to protect the privacy in the face of these kinds of technologies."

Stanley said because genetics experts have told him it inevitably will become easier to test DNA, "we need legal frameworks to figure out how to protect privacy in the face of this." For example, silicone chips from biophysicist Stephen Quake's lab at the California Institute of Technology, in Pasadena, could in the next 10 years sequence an entire person's genetic code cheaply and in a few days, he noted.

"I don't think anybody objects to samples from crime scenes. I think using DNA to catch murderers is a fine thing," Stanley said. "But we need to be cognizant of greater implications. We're going to be facing issues about how to keep DNA private from lawyers, governments, insurance companies, even nosy neighbors. It raises issues of employment discrimination, because employers have a natural incentive to hire healthy workers, and always have an incentive to discriminate against you by DNA, as long as health insurance is provided by the workplace."

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He added: "Or think about schoolchildren checking out each other's genetic profiles, or having profiles posted on the Internet. The fact is, there are heavy incentives to collect this information."

Electronic Frontier Foundation staff technologist Dan Moniz said he thinks the technique could be helpful to nab crooks, but he wonders about further implications in law.

"People already have fingerprints taken of them. Will it just become part of the standard booking procedure? Will you be notified that they're taking DNA? Can you refuse to give fingerprints if you don't want DNA taken?" he asked.

Moniz told UPI there are four directions he would like to see the question of DNA collection from prints go. "First, I want to know who's using this technology. I want to be notified right up front, at the police department, hospital, HMO, anything. No surreptitious extraction," he said.

"I should have a right of refusal and I should receive no special treatment if I do refuse it," he continued. "Finally, I should have a clear statement of who has full control of it, to make sure it does not get (contracted) out."

Moniz said the problems of outsourcing the collection of genetic information is a violation of privacy that goes beyond the potential for discrimination. "Will you get marketed on a genetic level? To be somewhat facetious, is this a new piece of the puzzle of the already omni-present spam about penile enhancement?"

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Although the method "can be used for DNA identification for sure," Viaznikova said -- people have stretches of inactive "junk DNA" whose patterns are as unique to them as their fingerprints -- she added that her group also has a more ambitious goal for their method: extracting enough undamaged DNA from fingerprints to study the active DNA that actually drive survival.

"Our interest is in the heart. If a patient goes to a doctor, in future perhaps the doctor can identify if a person has some kind of gene that can one day lead to heart failure," Viaznikova said. "We think we can use our technique for DNA profiling. It's not proved yet, but we're going to try and do it."

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