DNA Evidence Can Be Fabricated, Scientists Show

[Sarad AV]

pay a visit to the barber. wait till he dumps all the hair. get a few strands and you are done. why bother to duplicate dna.

Sarad.


--- On Tue, 8/18/09, Eugen Leitl <eugen at leitl.org> wrote:

> From: Eugen Leitl <eugen at leitl.org>
> Subject: DNA Evidence Can Be Fabricated, Scientists Show
> To: tt at postbiota.org, cypherpunks at al-qaeda.net
> Date: Tuesday, August 18, 2009, 2:15 PM
> http://www.nytimes.com/2009/08/18/science/18dna.html?_r=1&pagewanted=print
> 
> August 18, 2009
> 
> DNA Evidence Can Be Fabricated, Scientists Show
> 
> By ANDREW POLLACK
> 
> Scientists in Israel have demonstrated that it is possible
> to fabricate DNA
> evidence, undermining the credibility of what has been
> considered the gold
> standard of proof in criminal cases.
> 
> The scientists fabricated blood and saliva samples
> containing DNA from a
> person other than the donor of the blood and saliva. They
> also showed that if
> they had access to a DNA profile in a database, they could
> construct a sample
> of DNA to match that profile without obtaining any tissue
> from that person.
> 
> bYou can just engineer a crime scene,b said Dan Frumkin,
> lead author of the
> paper, which has been published online by the journal
> Forensic Science
> International: Genetics. bAny biology undergraduate could
> perform this.b
> 
> Dr. Frumkin is a founder of Nucleix, a company based in Tel
> Aviv that has
> developed a test to distinguish real DNA samples from fake
> ones that it hopes
> to sell to forensics laboratories.
> 
> The planting of fabricated DNA evidence at a crime scene is
> only one
> implication of the findings. A potential invasion of
> personal privacy is
> another.
> 
> Using some of the same techniques, it may be possible to
> scavenge anyonebs
> DNA from a discarded drinking cup or cigarette butt and
> turn it into a saliva
> sample that could be submitted to a genetic testing company
> that measures
> ancestry or the risk of getting various diseases.
> Celebrities might have to
> fear bgenetic paparazzi,b said Gail H. Javitt of the
> Genetics and Public
> Policy Center at Johns Hopkins University.
> 
> Tania Simoncelli, science adviser to the American Civil
> Liberties Union, said
> the findings were worrisome.
> 
> bDNA is a lot easier to plant at a crime scene than
> fingerprints,b she said.
> bWebre creating a criminal justice system that is
> increasingly relying on
> this technology.b
> 
> John M. Butler, leader of the human identity testing
> project at the National
> Institute of Standards and Technology, said he was
> bimpressed at how well
> they were able to fabricate the fake DNA profiles.b
> However, he added, bI
> think your average criminal wouldnbt be able to do
> something like that.b
> 
> The scientists fabricated DNA samples two ways. One
> required a real, if tiny,
> DNA sample, perhaps from a strand of hair or drinking cup.
> They amplified the
> tiny sample into a large quantity of DNA using a standard
> technique called
> whole genome amplification.
> 
> Of course, a drinking cup or piece of hair might itself be
> left at a crime
> scene to frame someone, but blood or saliva may be more
> believable.
> 
> The authors of the paper took blood from a woman and
> centrifuged it to remove
> the white cells, which contain DNA. To the remaining red
> cells they added DNA
> that had been amplified from a manbs hair.
> 
> Since red cells do not contain DNA, all of the genetic
> material in the blood
> sample was from the man. The authors sent it to a leading
> American forensics
> laboratory, which analyzed it as if it were a normal sample
> of a manbs blood.
> 
> The other technique relied on DNA profiles, stored in law
> enforcement
> databases as a series of numbers and letters corresponding
> to variations at
> 13 spots in a personbs genome.
> 
> >From a pooled sample of many peoplebs DNA, the
> scientists cloned tiny DNA
> snippets representing the common variants at each spot,
> creating a library of
> such snippets. To prepare a DNA sample matching any
> profile, they just mixed
> the proper snippets together. They said that a library of
> 425 different DNA
> snippets would be enough to cover every conceivable
> profile.
> 
> Nucleixbs test to tell if a sample has been fabricated
> relies on the fact
> that amplified DNA b which would be used in either
> deception b is not
> methylated, meaning it lacks certain molecules that are
> attached to the DNA
> at specific points, usually to inactivate genes.