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Science

DNA Extraction From Fingerprints 224

Posted by michael from the gattaca-wasn't-pessimistic-enough dept.
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."
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DNA Extraction From Fingerprints More

DNA Extraction From Fingerprints

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  • This is good... (Score:4, Interesting)

    by PakProtector ( 115173 ) <cevkiv@@@gmail...com> on Saturday August 02, 2003 @12:19AM (#6594203) Journal
    ...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.

    • Re:This is good... (Score:4, Funny)

      by fireboy1919 ( 257783 ) <(rustyp) (at) (freeshell.org)> on Saturday August 02, 2003 @12:25AM (#6594234) Homepage Journal
      Sure, it seems good now, but what about thirty years from now?

      By then the genetic revolution will have happened, and only those approved using the sophisticated government-run breeding program will be able to have children, and even those will be genetically modified to have the best traits. With stuff like this, it will be almost impossible to fool the robot-search droids, who will be able to identify you in an instant as a "mutt" whose parents concieved you out of love, not mandate.

      I ask you, would YOU want to be one of the ones sent to the extermination chamber for the "good" of society because your actions are unpredictable? I think not. We need to nip this in the bud while we still can, just as we need to nip the robot-search droid projects in the bud as soon as they come up.
    • Senator: well, now we can cross that out of the Patriot act.

  • Court-admissible (Score:5, Interesting)

    by joelt49 ( 637701 ) <joelt49 AT yahoo DOT com> on Saturday August 02, 2003 @12:19AM (#6594206) Homepage
    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.

    • Re:Court-admissible (Score:5, Interesting)

      by cybercyph ( 221022 ) on Saturday August 02, 2003 @12:22AM (#6594218)
      finger prints are uniquely identifying, but often times they themselve's are unidentifiable...if they are smuged, or incomplete. DNA extracted from a smudged fingerprint could be used to identify the print's owner
      • How would you know the DNA belongs to the owner of the original print, or a person who may have smudged the print?

    • Re:Court-admissible (Score:4, Interesting)

      by bmajik ( 96670 ) <matt@mattevans.org> on Saturday August 02, 2003 @02:22AM (#6594544) Homepage Journal
      you know, i want really badly to agree with you. What everyone wants is some black and white way to know beyond the shadow of a doubt that its time to put away some repulsive violent criminal. Who wouldn't be 100% in favor of putting away rapists every time ?

      When i first heard about people protesting DNA evience i was really outraged because it seemed to easy, so black and white, to get convictions that were difficult or impossible otherwise.

      Upon reflection, im greatly worried. If faith in DNA evidence is unquestioning then i worry that any way it is used at all becomes an upen and shut conviction.

      Consider the scenario that my friend hands me a gun, then 2 hours later uses it in a glove job. My finger prints are on the gun. My DNA matches those in the prints _exactly_.

      Here's what the jury will hear:
      "The irrefutable DNA evidence links the defendant with the murder weapon."

      a more realistic and frightening scenario, perhaps, was used in the mid 90s hollywood production, "The Crush". The teenage girl with an unhealthy fixation on the man renting the room from her parents fishes a used condom out of the trash and manages to insert the expelled semen into herself. She fabricates a rape story and the police have evidence of semen inside her body that is of course a perfect DNA match...

      reliance upon technology to determine what did or didn't happen will continue to increase. the risk is that the application of this information will be misused. I do not trust a jury to have healthy skepticism of the CIRCUMSTANCES that produce a DNA sample in light of the fact that a DNA _match_ is 100% irrefutable identification and makes the job of being a good juror so ... easy ..

      think about where you are leaving your dna and how you might be implicated by it..

    • 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.

      The opposite is actually more likely to occur. The mere presence of DNA "evidence" can induce judges and juries to stop thinking altogether.

      In the case of illegaly obtained confessions, the mere presence of a "confession" (even when it gets stricken from the record) is usually enough to get a conviction. Unfortunately, what most people don't realize is that

    • 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.
      Well, I for one think it would be a pretty good idea to establish the reliability and limitations of this technique before using it to lock people away. Especially me.
    • 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.

  • big brother (Score:3, Insightful)

    by cybercyph ( 221022 ) on Saturday August 02, 2003 @12:20AM (#6594208)
    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...
    • could the government use this technique to start on their national DNA database?

      It would probably not be cost-effective to use this techinique for the purposes of compiling a large database. My guess is that it will only be used when needed.

      Someday in the not-very-distant future, law enforcement agencies probably will start compiling large DNA databases. However, this technique is not the revolution that will make that happen.
    • I don't know about you, but I've never been fingerprinted. Not for my drivers license, not for my job, never. Nor will I be. As far as I'm conserned mandatory fingerprinting violates both the 4th amendment right to be secure in ones person, and the 5th amendment right to not be compelled to be a witness against oneself.

  • Couldn't this be used for more than fingerprints? (Score:5, Insightful)

    by gotr00t ( 563828 ) on Saturday August 02, 2003 @12:21AM (#6594215) Journal
    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.

    • Re:Couldn't this be used for more than fingerprint (Score:5, Insightful)

      by ktulus cry ( 607800 ) on Saturday August 02, 2003 @12:26AM (#6594237)
      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.

  • Privacy (Score:5, Insightful)

    by questamor ( 653018 ) on Saturday August 02, 2003 @12:23AM (#6594220)
    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.

  • How does this help? (Score:4, Interesting)

    by groove10 ( 266295 ) on Saturday August 02, 2003 @12:23AM (#6594225) Homepage
    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.

    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?

    /me puts on his tin foil gloves
    • A smudged fingerprint, or one with damaged detail that's not able to match a fingerprint database by its distorted shape will be able to match via DNA instead.

      Just one more little tool. Not the whole solution to finding The Bad Guys, but it can help fill in a hole.
    • 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.

      • Re:A step backwards, actually (Score:2, Interesting)

        by Anonymous Coward
        " You can't plant a fingerprint."

        Actually you can. Anyone can make a mold of your finger and then use that to plant your prints around. This was just in a case on Dateline where a guy got a fingerprint from someone else out of plumbers putty in their house and made a wax mold to plant a bloody print. The only way the police knew the print was planted was because of how the blood was on the opposite part of the ridges that it would be on in a real fingerprint.
    • Does this indicate a move toward DNA databases instead of fingerprint ones?

      Yes, surely we're moving in that direction. All of our military personnel already has its DNA on file. And this information has already been used successfully to find and convict the *relative* of a retired veteran. So the question is, do you have a relative in the military? And if you do, you can bet the US government already has some of your DNA in its database. DNA profiling is what they call it. The problem is so bad, conspir

  • Spankin the monkey (Score:5, Funny)

    by NanoGator ( 522640 ) on Saturday August 02, 2003 @12:23AM (#6594226) Homepage Journal
    Yeah, we all know what the source of the DNA is on Slashdot users' fingerprints...
    • "Yeah, we all know what the source of the DNA is on Slashdot users' fingerprints... "

      Flamebait? *sigh* I really hate having to explain that a joke is a joke. It loses its funnniness. But if I don't explain it, it's flamebait. Argh.
      • Perhaps the moderator expected an argument to come of your comment. "I have a girlfriend!" "No you don't!" "In Soviet Russia, DNA collects you!"
      • Yeah, but that only contains 1/2 of your DNA. So you could put some argument behind it. Better yet. Before doing a crime, smear animal blood on your hands. Or wear gloves, a hair net, shoes with no tread that are several sizes too big, wear a 50lb bag of dog food on your back and wear a space suit. Hopefully that will get rid of 99% of that really hard to use evidence.

        • Re:Spankin the monkey (Score:5, Funny)

          by Dun Malg ( 230075 ) on Saturday August 02, 2003 @10:33AM (#6595468) Homepage
          Better yet. Before doing a crime, smear animal blood on your hands. Or wear gloves, a hair net, shoes with no tread that are several sizes too big, wear a 50lb bag of dog food on your back and wear a space suit. Hopefully that will get rid of 99% of that really hard to use evidence

          "Witnesses report that the suspect fled the scene on foot. Be on the lookout for an individual about 6 feet tall, wearing giant clown shoes, a space suit, bloody rubber gloves, and a large bag of Purina Dog Chow tied on his back."

          I just about crapped myself imagining this perp...

  • Oh great (Score:4, Funny)

    by martissimo ( 515886 ) on Saturday August 02, 2003 @12:24AM (#6594229)
    Now we're going to need tinfoil gloves to go with our hats!

    • Re:Oh great (Score:5, Funny)

      by Jippy_ ( 564603 ) on Saturday August 02, 2003 @12:35AM (#6594268)
      Now we're going to need tinfoil gloves to go with our hats!

      Thanlks forr teh sughestionm! Theyu workl gREAT!

    • Re:Oh great (Score:3, Interesting)

      by Rob Simpson ( 533360 )
      Nah, leather gloves should do fine. I bet they'll be surprised when they track the break-ins to Bessie the Mad Cow!

      Btw, since this uses trace amounts of DNA (I'm not sure where it comes from - only the bottom layers of skin cells are nucleated...glands, maybe?) why do they say there is less risk of contamination? Wouldn't it be greater? What if you just shook hands with someone - especially if they had a cut, or hyperhidrosis, or, ugh, had traces of semen or feces (including shed intestinal mucosa) on

  • So now I will have to wait for 15 minutes before the data-centre door opens?? ;-)

  • Not Good (Score:4, Interesting)

    by phatcat625 ( 668966 ) on Saturday August 02, 2003 @12:33AM (#6594265) Journal
    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.
    • If you testify in court that you were helping a stab victim, then it is not in question whether or not you were at the scene of the crime, you've already admitted you were. DNA evidence proving you were there is pointless.

    • Re:Not Good (no) (Score:4, Insightful)

      by zoloto ( 586738 ) on Saturday August 02, 2003 @11:38AM (#6595718)
      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.
  • Including the EFF, it seems. First, what's the big deal about having your DNA on file? It's just a blueprint for the body - individuality comes from the mind. So "the government" has a DNA listing for you...damn, there goes my your career as a rapist. Second, if you don't want your DNA cataloged don't leave it laying around. Wear gloves. And a hat. And a suit to catch falling skin flakes and eyelashes. And sneezes. And don't get arrested or take any jobs where a fingerprint is required.

    • Re:The tin foil hat brigade is out (Score:2, Insightful)

      by Anonymous Coward
      " 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.
      • Oooh, insurance is so evil. Guess what, if you hate it, don't buy it! Save your money for your catastrophic illnesses so you can pay it out of pocket, for the car accident that you cause.

        Insurance is SUPPOSED to exist to pay for catastrophic unknown and unexpected situations, not as a crutch to pay for every little thing that arises. Insurance is expensive and underwriting is strict because of attitudes like yours.

        Chris

        • Insurance is SUPPOSED to exist to pay for catastrophic unknown and unexpected situations, not as a crutch to pay for every little thing that arises.

          While this is very true, it seems a bit misplaced in response to the post you answered to. I am not so sure breast cancer belongs to the class of "every little thing that arises". In fact I'm quite sure that anyone affected directly or indirectly would rather classify it as a "catastrophic unknown and unexpected situation."
          But maybe you were just trolling.

        • Oooh, insurance is so evil. Guess what, if you hate it, don't buy it!

          Well, actually it is -- okay, maybe not evil, but unworkable. The whole idea of insurance is based on the assumption that bad things can't be predicted in advance. As medical science and DNA techniques become more widely used and reliable, this assumption becomes less and less true. Eventually every genetic disease will be predictable with 100% accuracy, at which point health insurance will be useless, because the only people who can

          • The whole idea of insurance is based on the assumption that bad things can't be predicted in advance.

            Heh. The thing about insurance that IS evil is the very nature of the arrangement. Paying the monthly premium on (for example) catastrophic health insurance is like placing a long-shot bet. What makes it evil is that you're betting that you might get sick/hurt, and then doing everything in your power to see to it that you lose the bet! Is that twisted, or what?

          • But health insurance pays for a lot more situations that ARE expensive but AREN'T related to genes - like childbirth and appendicitis, for instance.

            If you think about it, insurance is similar to credit cards...people COULD save their money and buy everything from their checking account, but they don't...they buy on their credit card and make monthly payments on that. Insurance works the same way :)

            You're talking to a future CPCU (www.aicpcu.org), btw :) I'm also an insurance agent for one of the top 5 com
      • 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?

        Should they? Insurance is based on probability, actuarial tables and all that. That's why when you get life insurance, for example, they ask your age, sex, if you smoke, if you have a family history of heart disease, and you may even be required to get a check up. That's also why insurance for an 80 year old is much more expensive than it is f

  • Makes one hope for certain things (Score:2, Insightful)

    by Anonymous Coward
    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

  • Gattaca (movie) (Score:5, Insightful)

    by heli0 ( 659560 ) on Saturday August 02, 2003 @12:59AM (#6594333)
    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.

    • Re:Gattaca (movie) (Score:4, Insightful)

      by Peyna ( 14792 ) on Saturday August 02, 2003 @03:29AM (#6594682) Homepage
      Of course, just being somewhere doesn't prove anything. If a guy's wife is killed in his house, his DNA is going to be all over the place; so they won't prove anything. Heck, they'd probably find his DNA on her even if he hadn't had contact with her in a few days. If they find his DNA on the murder weapon or something; that's a different story; but sucking up everything in site and seeing who was there doesn't always tell you much.
  • could the government use this technique to start on their national DNA database? scary thought...

    Wouldn't a national DNA database be a good thing? How many crimes go unsolved even when DNA is found but no match is made? How many people have been released from death row because of advances in DNA tech that didn't even exist when they were wrongly put away? More information is a good thing, people!

    Sure.... a few people may misuse it. Maybe my insurance company will raise my tab because they see I carry a
    • What if you find yourself out of a job and unable to find another because your employer sees that you carry a gene for heart disease and doesn't want to pay for your inflated health insurance premiums? What then?
    • Where does it end? Where do you draw the line? I hate to get all Minority Report cliche-ish on ya here, but it really is a slippery slope.

      You use the health/insurance example very astutely (especially compared to the other post I replied to), but insurance companies are private organizations you can choose to do or not to do business with. You do not have this option with the federal government. What if they run your DNA through the database and find that you're related to three murderers and the computer
    • 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 comp

  • Digital identity (Score:5, Insightful)

    by vkg ( 158234 ) on Saturday August 02, 2003 @01:11AM (#6594373) Homepage
    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 [idcommons.net] 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?

  • DNA not used for proving guilt (Score:4, Interesting)

    by nsideops ( 579890 ) on Saturday August 02, 2003 @01:20AM (#6594396)
    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.
  • I have one thing to say: When X-Ray was invented, there was wide misunderstanding about what it could and could not do and so some women started going to bath with their clothes on because they were afraid of being photographed through the walls.

    My point is that it is never the technology itself that is bad. It's surprising that /.ers who can see this so clearly in the case of p2p are the ones clamoring against it whenever anything infringes privacy. Don't oppose technology, oppose oppressive governments

  • DNA copy rights? (Score:3, Interesting)

    by Alien Being ( 18488 ) on Saturday August 02, 2003 @01:34AM (#6594441)
    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?
  • I'm pretty sure photographic evidence exists of the Jack The Ripper killings from the late 19th century, and maybe some physical evidence still exists as well. I'm not up to date, but I think it's currently pretty well accepted that the killer was one of about 7 individuals. Furthermore, most/all of these individuals were well known identities, and I'd expect their descendants would be easy to track down.

    If they could extract DNA evidence from artifacts of the Ripper killings, they could extract DNA from
  • but i wish they would develop a DNA test that can give you results faster than 1-2 days.
    If they can cut it down to a couple minutes or even a couple hours that would be fantastic.

  • Proof, Sampling Errors, and Racial Differences (Score:5, Interesting)

    by nhaze ( 684461 ) on Saturday August 02, 2003 @07:23AM (#6595014)
    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.

  • And again... (Score:3, Interesting)

    by Snaller ( 147050 ) on Saturday August 02, 2003 @08:58AM (#6595202) Journal
    ... 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...
  • I mean DNA extraction from crime scenes is already routine (for serious crimes). Of course we already also have the techology to sequence DNA and identify the genes. I wonder how long before they can use that information to build a computer model of the donor's expected physical appearance? It can't be that far off.

    Then eventually there will be portable devices, routinely carried by police officers, which upon "tasting" a fingerprint or a discarded hair follicle or the like, will be able within a matter of
  • There are two things doing stabdard microsattelite (STR) dna analysis requires. 1. Sufficient quantities of DNA, and 2. sufficient quality. By quality what people are referring to is how fragmented the DNA is. By no means, when one extracts DNA do you expext 46 several hundered million base long strands of DNA. Depending on how prisitne the sample is (is it fresh, has it been burned, was it exposed to tons of sun, has it been frozen, is it just pplain old etc...) you are likely looking at, in bad bad ca

  • Numbers (10 ng) don't make sense to me (Score:3, Interesting)

    by a-aiyar ( 528921 ) on Saturday August 02, 2003 @09:56AM (#6595358) Homepage
    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!

  • what if... (Score:2, Interesting)

    by Ian 0x57 ( 688051 )
    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.
    • DNA, to present, is not used as the sole factor in a conviction. It can be used to prove, when there is a lack of other evidence, that a person *wasn't* there, but that's about it.

      Factors like motive, alibi, eyewitnesses, and general forensics matter an awful lot more than sifting the whole crime scene for random DNA. In a murder scene, they can tell the murderer's height, handedness, time of the crime, etc, just from the angle of the bloodsplats on the walls and the wounds/bruises/markings on the corpse.
  • Let's say you need .1 nanogram of DNA to do the analysis, but you only recover .01. Is it possible to clone or grow DNA in a vat to build up the amount?

    I really have no idea how the "wet sciences" work...just curious.

  • Did dinosaurs leave fingerprints?

    On the slightly more serious side, I wonder if this advances technologies used in getting intact DNA from smaller samples of older stuff, with the eventual aim of getting enough to clone something that's not around anymore.

  • A lot of people aren't thinking this through. They aren't saying they can extract DNA from an image, fax, photograph, or digitization of a fingerprint. They're saying they can extract DNA from the fingerprint itself, because of residue left from the actual finger. This isn't high-tech palmreading.

  • Effective Counter to this ... (Score:3, Funny)

    by fygment ( 444210 ) on Saturday August 02, 2003 @07:53PM (#6597565)
    ... 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.

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