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DNA extractable from fingerprints
By Charles Choi
UPI Science News
Published 7/31/2003 9:30 AM
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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.
"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."
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."
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."
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?"
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."
Copyright 2001-2003 United Press International
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