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DNA Extraction From Fingerprints
Myriad writes "A Canadian scientist has developed a new way of gathering DNA evidence for analysis using fingerprints. The new test can extract DNA in 15 minutes - even from a print stored for many years and in varying conditions. The patented extraction technique consistently produces ~10 nanograms of DNA. Analysis generally requires 5-10 nanograms, although it is possible with as little as 0.1 nanogram."
...as I think it will seriously make finding the guilty easier, and seperating the innocent from the guilty. If I'm not mistaken, it currently requires a judge's order in the united states to collect a DNA sample. Now all you have to do is dust something touched by the suspect to get a DNA sample.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
You always have the problem of getting it admitted in a US court. Expect big battles over this. For example, if the judge isn't the most tech-savvy judge around, someone could bullshit him/her into believing that the DNA samples are unreliable. Also, you have the BigBrother concern. However, fingerprints are already considered uniquely identifying. The only added problem w/ getting DNA from fingerprints is technology that is still years away, if it even comes to the market -- predicting people's characteristics/future death from DNA. However, the only reason to get the DNA from the fingerprint and not from the sweat that the person left, or the hairs that the person left, etc., is because of the storage factor. So, while people worry about their DNA being extracted from a fingerprint, they should be more worried about all the hair follicles and skin cells they are leaving behind that also give away their DNA.
this brings up scary issues...think how many times you've been finger printed...cashing checks, getting a driver's liscense...many people bring their children in for fingerprinting, in case of kidnapping or incase the child somehow gets lost. I, and many of those parents would never think to let the government have their or their child's DNA on file. could the government use this technique to start on their national DNA database? scary thought...
Fingerprints are created by cellular residue rubbing off from the skin, and this process collects these in order to extract the DNA. However, why would this be labeled exclusively in use for fingerprints? Couldn't the process be used for almost any surface that a person has had direct contact with? This might also have many problems with contamination with the DNA of other cellular residue.
I have to say I gave up on any thoughts of privacy not long ago with the way technology is moving towards nabbing bits of DNA. This is just another jump forwards.
Not only can DNA be grabbed from a scene, but when cross referenced with the fingerprints that it was derived from, an ID can be made -without having you there- to compare from.
OK, so it's also possible that there could be contaminated DNA on your fingerprints, but all the same it looks like it'll be a strong enough match to be able to give whoever is analysing the DNA a bigger lead than just a fleck of skin or hair left at a scene.
If you already have the fingerprint, why do you need the DNA? Most criminals (or at least those arrested and brought to jail) are processed via fingerprints and that is what's stored.
/me puts on his tin foil gloves
Does this indicate a move toward DNA databases instead of fingerprint ones?
Will this save any time or effort on the part of law enforcement agencies?
Will newborns have their DNA sampled shortly after birth?
MMORPG fan-boy? Prove your worth
Yeah, we all know what the source of the DNA is on Slashdot users' fingerprints...
"Derp de derp."
Now we're going to need tinfoil gloves to go with our hats!
This technology can be and is used for more than just fingerprints. The article says that this technology isn't new - the Canadian just came up with a better way of doing it. As far as contamination, other cellular residue is easily spun out, you buy kits for that, that part is fast and cheap. The main thing I would be worried about is the purity of the sample as far as number of sources of DNA. Lots of people touch alot of the same things.
This could possibly lead to more false positives than now. Say you try to help a stab victim. If you touch the person your DNA will be on them and it's possible that you could be implicated for the murder.
Did anyone read this story and immediately think of how they just vacuum the entire crime scene and run every piece of debris through an instant DNA test? The first time I saw that I thought it was 50+ years away; now I would be suprised not to see it within a decade or two.
Whenever the offence inspires less horror than the punishment, the rigour of penal law is obliged to give way...
current dna testing relies on "marker" regions which are supposed to be present in a unique combination for each individual. however, because this is not a whole sequence comparison, there is a small chance of a false positive error but smaller than that of false positives using fingerprints. Indeed the marker regions were selected because they were (relatively) fast to test and did not give away information about the suspect (eg. race or eye colour, although one of the markers was later found to be linked to diabetes).
i think that this technology will eventually find its way into our courtrooms, and this is good. what would be bad is if we thought that any technology was so perfect that we didn't need a trial and we could go out hunting bad guys on their dna evidence alone.
there is no substitute for a public trial where all the evidence gets laid out on the table and a reasonable judge ensures that all parties are treated fairly. if that doesn't happen for the least of our citizens, then it's time to go find another country to live and work in. I've moved countries twice, and i'm always watching with my overnight bag under my desk.
beyond crime there are benign uses for dna identification. the Army DNA registry would also serve as a way to identify the dead, who have been blown up beyond recognition. this gives valuable closure for families and loved ones.
paternity testing now requires that you have a live man to take a sample from. with this new tech you could get the dna fingerprint from the inside of a locket or something.
the way i see it, leaving dna is like a form of subconscious, automatic grafitti. we are always tagging our environment with the words "i wuz here."
it's just that these days, there might be people around who care to read it.
No pun intended, but this is really why the fight over who owns your personal data is so fookin' important. In ten or twenty years, the decisions made today about who owns your medical records, which databases can be legally connected or correlated and who the FBI has to talk to to see that data are going to vitally effect our civil rights on a scale we can't quite imagine.
It's not unreasonable to imagine that in 20 years it will be as easy to pick up your identity from a retinal scan, a fingerprint or even trace DNA is it currently is to pick up your identity from your credit card or your supermarket discount card, and if we don't have more stringent policies around handling of personal data we're all screwed. There's no place to hide when your body constantly sheds ID packets. Your cells are you.
Identity Commons is trying to get some stuff off the ground using a "governance-based" identity system: where the people who's identities are being stored actually get to vote on how the system is run.
It's an interesting idea, and might (in the long run) offer some answers to that age old question: who watches the watchmen?
Hexayurt - open source refugee shelter,
I'm certanly no expert, but I understand it's extreamly more difficult to prove guilt based on DNA evidence. It's more often used to prove innocence or provide that shadow of a doubt. This technology could greatly help in lowering the chance of someone being falsely prosocuted for a crime.
Teach someone to use the net and they won't bother you for weeks; show them Slashdot and you may never see them again.
Large databases are being built up of fingerprint data and now DNA data. The acuracy of this data is at best questionable. Fingerprints are measured at 16 points. From this you do not get 16^16.
I think that if you measured fingerprints to an infinite acuracy you may find the theoretical infinate number of fingerprints required to sustain the myth that no 2 fingerprints are the same but here in the real world we measure a finite number of points and therefore have a finite number of prints and as the database reaches that number there must be mistakes.
The mistakes are already happening with DNA and because this evidence is perported assumed to be infallible innocent people are being arrested.
If this evidence was only used to support other evidence I would see it as a good thing but when it is used as the only evidence then it is very bad.
I think that in the future this DNA witch hunt will be seen for what it is but for now innocent people will be caught up with the guilty.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
DNA extracted from the region of a fingerprint does not prove that the DNA came from the fingerprint.
Residual DNA coats every surface and depending on the environmental conditions, whether it is inside or outside exposed to the sun, many other sequences will be present.
Current sampling and extraction techniques can not avoid this contamination and if your favorite hangout turns out to be a murder scene, well you are in trouble. While control samples taken at the scene in areas where 'no fingerprints' occur can be taken to test background DNA, it certainly is not foolproof.
Additionally, races and skin types slough skin at different rates and have significant oil-content differences, so there will also likely be a discrepancy in who gets caught. tough luck.
I have a hard time believing that they can extract 10 ng of DNA from a fingerprint. A diploid human cell as 6x10e9 bp of DNA. One bp is 660 daltons. Calculating backward, 6x10e9 bp works out to being 6.6 pg of DNA.
So for them to extract 5-10 ng of DNA from a fingerprint, a fingerprint needs to contain between 1000 - 2000 cells. I work with epithelial cells, and a 1000 - 2000 cells is a fairly large patch of cells.
So either they mean that they get 10 ng of PCR amplified DNA (which is possible), but then is hardly representative of the entire genome, or they are using fingerprints from people who are really shedding skin!
You say:
This is only true if you get a sufficiently large number of fragments. If you're analyzing someone's entire genome, of course you're right -- the only possible way to get an identical "DNA fingerprint" is on identical twins. But in fact the number of fragments analyzed is fairly small, in the thousands; which means it's possible to get the same analysis out of several million unrelated people, and a much smaller number of closely related people. Considering how many crimes are committed by one family member against another, this is a real concern.
I'm all for DNA analysis as a forensic tool, since it's currently the most accurate tool we have for placing a suspect at the scene of a crime. But it's a long way from perfect. Presumably, as the technology improves and it becomes practical to analyze larger sequences faster, it will get better.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
not getting into what I do in my profession, this is almost completely wrong. A lot more goes into a police investigation than just the dna evidence. If that were true, your grandmother and my sister who touched the same steel bat in the sports store could be implicated if that bat were ever used to beat the tar out of someone.
Sorry to have to correct you, but that statement of yours isn't very accurate.