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Scientists Learn To Fabricate DNA Evidence

Hugh Pickens writes "The NY Times reports that it is possible to fabricate blood and saliva samples containing DNA from a person other than the donor, and even to construct a sample of DNA to match someone's profile without obtaining any tissue from that person — if you have access to their DNA profile in a database. This undermines the credibility of what has been considered the gold standard of proof in criminal cases. 'You can just engineer a crime scene,' said Dan Frumkin, lead author of the paper. 'Any biology undergraduate could perform this.' The scientists fabricated DNA samples in two ways. One requires a real, if tiny, DNA sample, perhaps from a strand of hair or a drinking cup. They amplified the tiny sample into a large quantity of DNA using a standard technique called whole genome amplification. The other technique relies on DNA profiles, stored in law enforcement databases as a series of numbers and letters corresponding to variations at 13 spots in a person's genome. The scientists cloned tiny DNA snippets representing the common variants at each spot, creating a library of such snippets. To prepare a phony DNA sample matching any profile, they just mixed the proper snippets together. Tania Simoncelli, science adviser to the American Civil Liberties Union, says the findings were worrisome. 'DNA is a lot easier to plant at a crime scene than fingerprints,' says Simoncelli. 'We're creating a criminal justice system that is increasingly relying on this technology.'"

3 of 256 comments (clear)

  1. You can pry my TAQ out of my cold, dead cycler by interkin3tic · · Score: 5, Informative

    Whole genome replication seems to mostly center around Polymerase Chain Reaction (PCR). PCR is an incredibly versitile technology. PCR machines cycle test tubes through specific temperatures, the thermal cyclers are cheap compared to a lot of lab equipment but still in the thousands of dollars. To do a PCR also requires some type of polymerase, nucleotides, some solutions, and short primer oligonucleotides. These are all items that aren't prohibitively expensive but aren't household items either.

    Maybe I'm being too ACLU/tinfoil hat, but I'm getting a sinking feeling that someone eventually is going to try to slap some regulations on PCR, or at some point in the future, having access to a thermal cycler and PCR materials is going to be seen by law enforcement as a reason to be suspicious of you. And I think that would be a real crime. I could see a future where thermal cyclers come down in price even more, maybe high school kids will start tinkering around with PCR as kids from yesteryear played with chemistry sets before we decided they could be used to make bombs and should be banned.

    Maybe not. Anyway, I think we should nip it in the bud if there's any hint that law enforcement starts thinking you need to have a good reason to manipulate DNA, just so they can keep their evidence unquestionably true.

  2. Re:And I'll be the first to say: by maxwell+demon · · Score: 5, Informative

    Well, here in Germany, the police has searched quite some time for the "phantom of Heilbronn" - a women which apparently was involved with a lot of otherwise unrelated crimes at very different places. Well, after several years it turned out that the DNA was not from someone involved in the crime, but from someone involved in fabricating the cotton buds used to take the DNA probes.

    --
    The Tao of math: The numbers you can count are not the real numbers.
  3. Re:And I'll be the first to say: by mcgrew · · Score: 5, Informative

    It's usually the cops who do the framing. An example is right here in Springfield, where two cops were caught planting cocaine. Details of that one from the Illinois Times:
    Springfield's worst nightmare
    Man who beat cocaine rap sues the city; whistleblower's case survives
    City's legal bills for ex-cops' defense expected to soar
    LEGAL BILLS MOUNTING

    Our cartoon city is, of course, paying for the crooked cops' defense. The news that DNA evidence can be fabricated is frightening; they need to go back to fingerprints. Of course, if you want to frame someone, cocaine is a lot easier to plant than DNA.