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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.'"
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.
At the moment most (if not all) DNA profiling is done by examining STRs. STRs are specific spots in your DNA where a certain pattern of DNA is repeated a number of times. And the number of times it's repeated might be different for you from the STR at that spot from someone else.
So if you check many of these spots, you can make it extremely unlikely that someone else has all of these spots with the same number of repeats as you do. In the US they check 13 loci. And this fake DNA (the stuff they advertise as being possible to make just by looking in the database, with no original genetic material) is just a load of these loci, with the correct number of repeats in there.
The reason it isn't much of a problem is that the technological bottlenecks that made the human genome project such a money pit are close to gone now. Taking a genetic sample and fully sequencing it shouldn't be that much of a problem in the next few years (I mean you can already do it for the price of a coat. To proof against fake evidence, many other SNPs or STRs can be checked instead, as a confirmation. Keeping a list of another 13 STRs to be used as confirmation would be a good start, having the loci known but not recording the results in databases to prevent this kind of counterfeiting.
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.
http://en.wikipedia.org/wiki/DNA_methylation makes it sound, to me, that it's probably do-able in a lab (very difficultly), or perhaps we can just get a way to bioengineer a strain of micro-organism to methylate certain areas and sequences as appropriate. Or, perhaps we can use enzymes in human cells that induce the appropriate methylation and find a way to make the enzymes function in vitro.
Either way, the methylation assay they've developed may be useful for now, but probably don't be for long.
Disclaimer: IANA-{genetic-engineer/biologist/biochemist}.
--TheOrangeSquid Is it any wonder things seem so awry? We swim in a sea of confusion and don't have to think to survive
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.
Free Martian Whores!
In most cases, they don't even have to say it in the first place. It's just a formality from a case where someone who actually didn't know their rights was railroaded. A good thorough law enforcement agent will read them as a matter of avoiding a technicality that could jeopardize evidence gained by your interview. In some jurisdictions, it's an automatic as a matter of policy.
However, if they do read it, and you do claim not to understand it, they can just place a public defender beside you during questioning and he can advise you on when to and when not to and how to answer. Outside of that, they should limit their questioning to what wasn't already known from outside entities (witnesses, evidence at the scene and so on). They do not have to limit the questioning to that though, it just means a possible challenge to anything gained that may or may not invalidate that portion of the evidence. The test would be a judge with some professional help determining if you actually did understand it or not. Very few people will not actually understand it unless the cops actually treat you like you do not have the rights as was the case in Miranda which lends it's name.
They can tell you that some criminal is out to kill you and the only way you'll survive is if you turn "state's evidence". They can tell you practically anything they want if they think it will make you talk.
They can lie to you. That's true. They can tell you that they found evidence implicating you. They could say they have a witness.
Misleading you to believe that you're caught is one thing. Presenting a situation in which you might confess to something you didn't do out of a fear for your safety is another entirely. That's coercion, its patently illegal, and any judge that's remotely capable would throw it out.
"But we have to pass the bill so that you can find out what is in it,..." - Nancy Pelosi