Scientists unlock DIY DNA Scientists in Tel Aviv say they've demonstrated that DNA evidence can easily be faked to match the wrong person - assuming the nefarious framer has access to a biology lab and DNA database. The boffins fabricated phony DNA using blood and saliva samples to match someone else's profile without any tissue from that person, …
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The writing's been on the wall for this for quite a while.
DNA evidence *by itself* may prove someone innocent but can't be relied on to prove someone guilty - all it proves is the the DNA was present. Unfortunately almost court systems assume that if the DNA is present then you have prima fascia evidence that the donor must also have been present too.
It's kinda like assuming that if you find an egg in the refrigerator ... then you must have had a hen in there too.
DNA - in its forensic role - has been Bad Science for a long time. Potentially at least.
The underlying principles are sound enough, and astonishingly valuable in non-criminal research and archeology. But the laboratory conditions necessary to grow and match samples - especially cultured samples - are exacting and not always achieved in the average forensic laboratory. Plus the statistical methods used to establish how certain the match is are often highly suspect - the odds against a false positive are nowhere near the millions to one so often claimed. It's a valuable tool for ruling OUT a suspect, but when making a positive match it's no more or less reliable in a court of law than any other forensic technique bought and paid for by a prosecuting body. In the end you're getting an expert opinion and no more - an expert opinion in the employ of the prosecution.
Personally, there are no circumstances whatever in which I'd ever convict a person on DNA evidence alone. But the police, courts, media and general public continue to treat this technique as though it was pure magic.
I don't really see this particular possibility as eroding the value of DNA evidence.
It would be a pretty unusual situation in which it was possible and worth the trouble to actually fake a sample of DNA when, as noted in the article, it's likely to be easier to find a real sample of some innocent's DNA.
Even if someone did want to create a fake sample from a particular individual to whom they had no access, they'd need to get hold of a DNA database record for that particular individual, which is unlikely to exist (unless a target has been chosen from a select few known to registered with some particular database).
"This will make life a LOT easier for defense lawyers."
Especially when UK.gov demands the construction of a DNA database (for crime prevention, you understand) and "publishes" it as part of a biometric ID card scheme (for crime prevention, you understand) and then "fixes" those pesky defence lawyers by issuing "guidance" to judges that DNA evidence should be considered as proof beyond reasonable doubt that there was indeed a hen in the fridge. (I, too, think this is a smashing analogy.)
I do believe it's already been said that the DNA database is going to be accessable to various "Research" bodies/companies (is already?)
And sure your average criminal may not have access, but your above average criminal may very well be able to gain access (think drug cartels, Politicos, rich people) if there's a way to get it done people with a will or money will do.
But what does it matter, DNA is the governments and polices new silver bullet and they wont give it up for anything.
Unless I'm missing the point of something, the second method surely requires access to not only the database, but the actual physical samples it refers to. Surely any lab would have (physical) security methods in place to guarantee the integrity of the reference samples, otherwise they're useless as evidence. Even if outside organisations were given access to information on the database, there's no way they'd be allowed access to the reference samples.
It's all very well creating a theoretical sample combined from a bunch of others, but you'd need to get your hands on the "up to 425" real samples to make something to plant...
IANAE but the last I heard the DNA database isn't a fully sequenced genome, but is based on a set of "markers" in combination. There have been various discussions about how many are needed and how statistically significant any result is. The more markers tested for, the more significant the results. There has been some criticism about too few markers being used.
Re. Framing Someone - all you need to know is the target's marker combinations, which is exactly what is on the DNA database. And we all know how secure these government databases are - so there's abolutely no change of this falling into the wrong hands. Now where's that tongue in cheek icon.....
From what I remember from studying this stuff at uni <cough> years ago, the process is basically.
1) Get DNA sample
2) Chop DNA into bits using specific enzymes. The enzymes target specific amino acid sequences, so you end up with various bits of DNA of different sizes all from the same sample.
3) Seperate out the different sized bits of DNA, normally using electrophorisis.
That 'map' of different sized bits is your DNA fingerprint.
So to frame someone you'd have to know thier DNA fingerprint, be able to get of the consituant bits of thier fingerprint, and then scatter the chopped up bits of DNA over whatever.
Just getting hold of the framee's DNA by getting hold a decent tissue\blood\saliva sample seems way easier.
I see this as a natural avenue for well-funded and well-educated (Russian, maybe?) organized criminals. They set up labs, much as they do heroin processing labs, and sell custom "results."
Sure, Bob the Burglar can't afford to set up his own DNA lab, but who wants to bet he wouldn't give Sergei ten thousand Euros to clear him from a rape charge?
@Gordon, um... my biochem paper hangs on my wall, too. However, in our PCR lab work even 20 years on, the enzymes didn't target amino acids, since that isn't what makes up DNA (come on, you can say it: deoxyribonucleic acid, not protein).
And I don't see where the folks promoted this fallacy discuss supplemental DNA analysis from mitochondria, a different genome, but would have to be a 'must match' between suspect DNA and collected evidence. Once again, did anyone ask a real biochemist about these tests and their meaning?
A lawyer friend sent me the paper this week, in a state of panic about the consequences,
As others have pointed out, if you have access to a subject's DNA profile and access to an oligonucleotide synthesiser then you could synthesise a DNA profile that matches a living individual and leave "evidence" at a crime scene. However it's going to be a lot easier to obtain DNA from an individual and scatter that around.
And if anyone thinks that the spooks don't pay attention to the purchasers of oligonucleotide synthesisers and of nucleoside phosphoramidites for those machines or to PCR systems and deoxynucleoside triphosphates for those machines then they are sixpence short of sixpence.
I don't really care about the difficulty/cost/likelihood of doing this; what I DO care about is that it CAN be done, and it is within the capacity of the state to do it.
Or does anyone STILL think our current rulers are wise, honest & benevolent?
If you do, or you still believe "I'm a straight kinda guy" then you deserve all you get.
I don't think it will be long and organized crime will start to see the benefit of working with DNA for the purposes of framing rivals (or even discrediting public officials they don't like).
Even if the victim of the frame manages to escape conviction, the nuisance value alone would be enormous.
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