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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.
So now I will have to wait for 15 minutes before the data-centre door opens?? ;-)
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.
Like in the next 5 to 10 years, the world will be run by thoughtful people who won't use technology like this to keep people under the thumb of government and industry.
Once you gain sufficient control over people you cross the line that divides governance from ownership. And I don't think human beings are sufficiently moral creatures to be trusted with the opportunity to own other human beings, whether it's outright ownership, or ownership implied in so many ways through the laws and practices of a society.
You can't plant a fingerprint. But you *can* plant somebody's DNA.
Then the prosecutor does his 1 in 10,000,000,000 lecture to the jury, and he's guilty!
Nevermind the fact that the DNA evidence could have been easily planted, if not at the crime scene, then at the lab.
We've seen this before. And not just with OJ.
Is this truly the only Earth I can live on?
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.
" It's just a blueprint for the body - individuality comes from the mind"
Tell that to the insurance company. If you have a genetic marker that gives you a 99% chance of getting breast cancer by age 50 do you think they will insure you?
I am sure the Nazis would have loved to have a DNA record of every German in the 1930's. It would have made it a lot easier to identify every Jew in the country.
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.
Can a person claim exclusive copy rights on their own DNA? Google turns up some firms offering such protection to celebrities. Are they just a scam? Could gene sequencers be classified as circumvention devices under DMCA?
With a process of this sensitivity, accidental contamination may become a serious problem. Did that billionth of a gram of DNA come from the perp's fingerprint or did it float into the room from somewhere else?
Call me crazy, but raise your hand if you saw Gattaca and thought "Gee, that's a bright and well adjusted future. What do you mean Dystopian?" I sure as hell did.
~
If you need me, I'll be hanging my computer from the
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.
They're gambling that I don't get sick. They're proving a service
Right, they are "gambling", but like a casino, they want to make sure that the odds are in their favour. When you take out an insurance policy, you are betting that the event will happen. The insurance company is taking bets from hundreds of people in the knowledge that the event is only likely to happen to a few people. So the lost bets from all the punters, pay off the few winners and give the casino a small profit. With the insurance company, all the policies from the customers, pay off the few claimants, and give the company a small profit.
Now, add in genetic testing, and suddenly you can see some of the cards before they have been dealt. Current testing can't predict with 100% accuracy what will happen in the future, but gives each party an idea which way the money will go. This is the equivalent of card-counting in a casino and see how popular that is with management.
The last thing an insurance company wants is a certain bet. A good example is taking out private unemployment insurance. There was once a guy who was notified one week in advance that he was about to be made redundant. He immediately called the insurance company for advice. They requested that he provide written details of the event in writing and they would send a claim form. Instead, they sent a letter in the post informing him that his policy was cancelled. While he was in employment, the small print stated either party could cancel the agreement with 3 days notice. If he had waited until being made redundant they would have paid out. Medical insurance companies aren't going to be any different.
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.
... we have a situation where only 0.000000001% of the people involved actually understand the Science - the rest just assumes "oh - they are probably right" - but if they are not, or have a hidden agenda.... don't let them tell you that one man can't make a difference...
If Google really cared they would fix Android Chrome to reflow text, instead of discriminating
Now, just because one has a copy of someone's DNA, that isn't enough. One diploid copy of human DNA is about 6.6 picograms. If that copu of the genome has been fragmented in one of the regions being amplified, the reaction won't work. True, you could get down into the 50 to 100picogram range for input DNA, but what you're doing is taking the statistics and throwing them out the window. Wheras the kits themselves give odds of matching a random person in the 1 in hundreds of millions to 1 in billions, if you're looking at say 100 copies of degraded DNA (0.6ng, or 600pg), you may only have on average 5 or so copies of intact DNA from the given amplification targets. Now the odds that you only see one allele (say from mom'a side) goes WAY up, because random luck might have caused only 1 or no copies of the other allele (from dad) to survive. The result is, you get an amplification that looks like the person has all one sized fragments for that region, whereas they may really have 2.
Don't get me wrong, I think this technology is probably tremendously useful, and can offer the ability to type people for all sorts of things, such as forensics. I merely wanted to point out some of the potential limitations of such a technique if the sample hasn't been stored well. I have a hard time believing DNA is super stable in black ink...
Just my random thoughts...
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!
I think you've taken a lot of urban legend and stuffed it into one big slashdot post.
DNA analysis by RFLP (Restriction Fragment Length Polymorphism) is very, very accurate. This is how it works:
On your DNA, you've got lots of little molecules. These molecules form a sequence. Every so often, there will be certain repeated sequences by chance.
Restriction Enzymes locate these sequences and go *snip*! They break down the DNA at these specific sequence points.
The DNA is then run through a gel - the smaller fragments go farther through the gel. The gel is then analyzed for the particular pattern of fragments in the gel.
In case you didn't catch the variabilty associated with all of this - these restriction fragments snip only at repeated sequences, repeated sequences which occur at random in our DNA. The chances of two people having exactly the same combination of restriction-snipped fragments is so so so so *so* small it is difficult to express in numbers - think about what you're saying.
There ARE cases of fallible DNA tests - DNA tests that aren't done properly, etc. But few people are ever jailed wrongly because of properly collected DNA evidence.
My biggest issue with DNA evidence is that it only proves that the suspect was at the scene, not that he commited the crime.
What if I touch a gun and 5 min later you kill someone with it. They might find my DNA but your fingerprints. If they are really good they will find both sources. Seems like resonable doubt to me. If they just go by finger print, closed case. Guess what I am saying is that they might find a bunch of DNA and have to release guilty people.
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.
If you are working with such small samples with nothing exta to verify against, how do you know you got a good sample? You don't. And the older the sample, or more public the collection location, the more like that there will be contamination. Reasonable doubt. Defendant Aquitted. Case Closed.
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.
... make sure your DNA is everywhere. Overload the system. Mail your dust to strangers. Travel lots. Touch everything in sight. Every time a test is done, you show up. Eventually they'll filter you out and voila! Invisibility through visibility.
"Consensus" in science is _always_ a political construct.
Fingerprints may be unique, but identification techniques aren't. That is unless, when you leave fingerprints do you so at a nice constant pressure, on a reasonably oil free surface. But as someone who routinely extracts nucleic acids as a living, I have a hard time beleiving the claims of extraction long after the fingerprint has been deposited. DNA isn't exactly heat stable, not to mention the legal disaster if you.. ahem.. had someone elses DNA on your fingers...