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New DNA Test to Solve More Cases 65

Posted by samzenpus from the you-can't-get-away-with-anything-anymore dept.
Krishna Dagli writes From the BBC,"Tens of thousands of unsolved crimes could be cracked with a new forensic technique, it has been claimed.The Forensic Science Service (FSS) is piloting a computer-based analysis system which can interpret previously unintelligible DNA samples.It claims the technique is a world first which will boost its crime detection rates by more than 15%.The method is being tested by the West Yorkshire, South Yorkshire, Northumbria and Humberside police forces."
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New DNA Test to Solve More Cases More

New DNA Test to Solve More Cases

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  • More Importantly... (Score:5, Insightful)

    by Quaoar ( 614366 ) on Wednesday October 04, 2006 @08:12PM (#16314611)
    ...it will hopefully free lots of people who have been falsely accused of crimes they didn't commit.

    • Re:More Importantly... (Score:4, Insightful)

      by geekoid ( 135745 ) <dadinportland&yahoo,com> on Wednesday October 04, 2006 @08:24PM (#16314745) Homepage Journal
      well, except for the dead ones.

    • Re:More Importantly... (Score:5, Insightful)

      by Hennell ( 1005107 ) on Wednesday October 04, 2006 @08:33PM (#16314849) Homepage
      That seems unlikely to happen; it seems to be more about reading "previously unintelligible DNA samples" then mending false positives. Not to mention that going into the 'solved cases' pile seems less high on their priority's then the 'cold cases' pile (Then again with prison overcrowding as it is, it could get higher on their list...)
      • (Then again with prison overcrowding as it is, it could get higher on their list...)

        Step 1: Remove non-violent drug offenders from prison
        Step 2: Insert the above into rehabilitation programs
        Step 3: ???
        Step 4: Profit

        I imagine Step 3 involves Gov't funds being given to (faith based) rehab programs

        As for this new DNA test, unless it is faster, cheaper and/or more likely to stand up in court, I don't see it as making a huge difference. From what I understand, DNA testing labs are already at/near max capacity.

        A
        • I don't know about speed, but what it does allow is a mixed DNA sample can now be broken apart into each person who left it.

          I am still not sure whether it is based upon sheer pattern matching (the UK has largest DNA database in the world) or if it is some other method.
          However in the news I have seen they are comparing cig butts and glasses for things - in my none expert analysis, these things are usually (though not always) single user items.
          What they haven't said is the real meaning, mutliple sperm samples

        • Re: (Score:3, Insightful)

          by malsdavis ( 542216 ) *
          "From what I understand, DNA testing labs are already at/near max capacity."
          Here in the UK where the research is being pioneered (but I persume it is the same for everywhere,) a large part of the reason for this is that so many DNA sources are contaminated, which means lots more testing for labs, which means capacity is reached sooner.

          So yes, it could make a huge difference. It is not expensive to test for DNA, it is expensive to test every single item possibly touched by the offender. If this technique mea
        • As for this new DNA test, unless it is faster, cheaper and/or more likely to stand up in court, I don't see it as making a huge difference. Well okay, even if it isn't faster, more reliable, more convincing, or helps to relive DNA labs of the large amount of work they have to do, it will still make a difference. If it happens to be more expensive or slower or requires more input (article doesn't say so), well then it only needs to be used on those cases the current system can't read. Maybe a better improve

    • Re: (Score:2, Insightful)

      by JaWiB ( 963739 )
      Yes, but how fast can this techinique be applied? Don't crime labs/law enforcement officials already have far too many cases to devote their time to?

    • ...it will hopefully free lots of people who have been falsely accused of crimes they didn't commit.

      Two problems: 1)The system/process will be made mostly available to "solving" crimes, not freeing criminals; it's bad prioritization politically, existing criminals could swamp the system, and if a guilty criminal were released after a false negative and was a repeat offender, there'd be hell to pay. 2)While a "maybe a match" will certainly be grounds for the police getting warrants and such, a "maybe no

      • Re: (Score:3, Insightful)

        by Qzukk ( 229616 )
        DNA match evidence is widely perceived as completely reliable by juries, public, judges, etc...and a less-reliable matching will erode that confidence.

        Absolutely right! DNA tests are 100% accurate and foolproof [chron.com]. The prosecutors say so themselves [truthinjustice.org]. In fact, this new test is so easy, all you do is push a button, and the screen lights up "guilty".

    • Re: (Score:2)

      by suv4x4 ( 956391 )
      ...it will hopefully free lots of people who have been falsely accused of crimes they didn't commit.

      It works the opposite way: when you claim there's a false positive, you'll get even less people to believe you, since now "we're 15% more accurate!".

      It's just like the lie detector, or monitoring your internet logs for looking up "teen" in google.

      Imagine if police could arrest you if your horoscope was certain you'll kill someone today and put you in jail. Crime "discoverability" will certainly raise when the

      • Re: (Score:1)

        by noigmn ( 929935 )
        "Imagine if police could arrest you if your horoscope was certain you'll kill someone today"

        Imagine how many people of that star sign would be killing people if the horoscope was right.

        • Re: (Score:2)

          by suv4x4 ( 956391 )
          Imagine how many people of that star sign would be killing people if the horoscope was right.

          Yup, arresting all those people in advance would be such a win for crime discoverability and prevention.

  • West Yorkshire crimes solved! (Score:4, Funny)

    by leehwtsohg ( 618675 ) on Wednesday October 04, 2006 @08:23PM (#16314719)
    West Yorkshire. A large number of crimes have recently been solved in this slumbering community. Using a new forensic technique, crime investigators were able to implicate most of the current police force in what was previously reported to be "unsolved" or "mysterious" crimes. 'As our DNA evidence clearly shows, the whole police department was involved in the crimes and their cover up. The crimes were then classified as "unsolved" to cover up their tracks. We have never seen such a wide spread of corruption.' Unidentified sources claimed that the are similar investigation of the police force in 3 other communities.

  • But if your suspect hasnt been taken into custody as of yet? Why not just 'swab' the entire world population.

    • Re: (Score:1, Troll)

      by 8ball629 ( 963244 )
      It isn't too far from the truth/future I'm sure. There will eventually be laws passed that will allow a huge database of DNA matched to records of people that both have and have not committed a crime, especially in the US if/when we're under Republican rule again. Once that law has gone into effect, newborns will probably be swabbed at birth and the rest of us will be swabbed the next time we register to vote.
      • What do you have to hide, citizen? Either you're with us, or you're with the terrists. Comply. Share and Enjoy.
        • Haha, obviously you're joking but the truth is I have plenty of things that I want to "hide" or atleast keep from the prying eyes of the government (nothing a DNA test would bring up).

          The government needs to take a few steps back in privacy and I think we all know that.

          • Re: (Score:2, Informative)

            by Anonymous Coward
            Here's the secret about DNA tests: They don't identify you.

            The original tests looked for a certain number of snippets of DNA that were considered "genes". Fewer than a dozen at first, but towards the end of this test's usage, they were up to about 16. With only 2^16 possibilities ("there or not there", 16 times), it matched you, probably your family members, and about 50 thousand other people, assuming that none of those snippets of DNA were actually the gene for having two arms or something like that, si
            • Yeah, so the future's trials don't look too different from today's but DNA is definitely more convincing to most people whether it really is reliable or not.

    • Re: (Score:3, Informative)

      by DrMindWarp ( 663427 )
      But if your suspect hasnt been taken into custody as of yet? Why not just 'swab' the entire world population. The UK has the world's largest citizen DNA database. Just about any encounter you have with the UK police, irrespective of your age and state of guilt or innocence, will result in your DNA being taken and integrated into their database. e.g. http://news.bbc.co.uk/1/hi/uk_politics/4720328.st m [bbc.co.uk]

    • Re: (Score:2)

      by Da3vid ( 926771 )
      The DNA matching isn't a 100% match. For example, most DNA matching techniques are highly accurate... say they're accurate to 1 in 250 million. Still, if you run a sample only by the USA database... on average, you'd have a wrong match every single search. Sure, it narrows it down... but it just isn't as simple as it sounds.
    • That's very nearly what is happening in the UK. Basically anyone who has any dealings with the police has a DNA sample taken, even if they are never charged with anything. And there are plans to fingerprint the entire population.
  • You mean the DNA tests for the past few decades havent been 100% ?!?

    This sounds like Intel's marketing department.

    • Re: (Score:1)

      by spvo ( 955716 )
      Its not saying the old DNA test are inaccurate. This technique just allows them to use DNA that previously they could not test, such as a DNA sample that multiple people had handled.

    • Re: (Score:3, Informative)

      by Ironsides ( 739422 )
      You mean the DNA tests for the past few decades havent been 100% ?!?

      The DNA can be a match and still not come from the suspect. All DNA is based on statistics.

      Marker A is in 0.25% of the population, Marker B is in 0.01%, C is in 0.3% and D is in 0.01% and E is in 1/3. That means that if someone has ABCDE they are 1 in 400,000. Granted, those aren't exactly real numbers and the tests can use over 10 different markers, but it gives you an idea of how the system works. Currently, it is impossible to s
      • DNA testing (in its ideal form) definitely works, as Ironsides describes, but the logistics of it are a bit difficult sometimes. I would not base a case solely upon it, especially if the opposition were to hire a lawyer to perform a Chewbacca defense with stunning, and fatal, precision. Another devastating obstacle is the thing of identical twins. If I wanted to live a life of crime, I would prefer to be an identical twin to someone, because in that case, DNA tests are basically rendered worthless.
        • Actually, the identical twins problem has occured before. Fortunately, the other twin has had an airtight alibi for where they were at the time of a crime. Sometimes they other twin happens to be in jail, sometimes out of state, but so far the case of which twin did it has not actually been a problem just yet.
    • No, it means that more samples are not rendered useless. Sounds like good science.
  • How do you face your accuser when it is a piece of software?
    • thats like saying "how do you face your accuser when it is a magnifying glass?" the computer is a tool being operated by detectives, it accuses no one of anything.
      • I think magnifying glasses are more varifiable than software. I can grind my own lens but I can't write a program that verifies another piece of software is correct, perhaps you can?
        • writing a program to verify to correctness of another program wouldnt solve anything. it jut introduces an infinite regression.

          if a case hinged on this one solitary piece of evidence, it would need to be thoroughly manually reverified to make sure it was accurate.
  • The ghosts of the many executed prisoners who are soon-to-be-exonerated applaud......sort of.

  • For you non-wetware workers (Score:5, Informative)

    by DrKyle ( 818035 ) on Wednesday October 04, 2006 @10:39PM (#16316029)
    DNA fingerprinting basically measures the number of repeat units at ~13 different locations in the genome. As you have 2 copies of your chromosomes you esentially get a unique 26 digit code. Looking at just one of the repeat locations, let's say the normal range is 8 to 12 repeats, so you can be an 8,8 8,9 8,10, 8,11 8,12 9,9 9,10, 9,11 9,12 10,10 10,11 10,12 11,11 11,12 or 12,12 (so there are 15 possibilities seen in the population, with generally similar frequencies for each). The chance of matching your sample with any randomly selected unknown will be 1 in 15, but if we go up to 13 different markers we have (1/15)^13 which gives a chance of any 2 UNRELATED individuals matching being about 1 in a quadrillion (more people than have ever lived, and likely ever will live). This means a match is a definite match, this doesn't mean evidence wasn't planted or some such conspiracy crap, but a match is a match, no chance of a collision like with 2 people having O- blood.

    The "new" stuff here is that they have come up with software which will allow the system to extract 2 sets of "seial numbers" from one reaction. Like having 2 fingerprints on top of one another and seperating them to determine the swirls. They also are claiming a more sensitive technique which will allow for smaller or partially degraded samples to be tested, but this is probably just tweaking the experimental protocol.

    This is no new test, just tweaks and algorithms.

    • Re: (Score:1)

      by delt0r ( 999393 )
      I'm affaid you are more or less completly wrong.

      Unfortunalty we are are all related to some degree and oh yes thats very important. It turns out that a set of good markers for Europe is not a good set for Aficans for example. Different ethinic groups have a different number of alleles in a different distrabution at a givin site for a start. Its not bloody loto, this is population genetics.

      Infact most tests hover around the 1 in 3 million of a random person beign the same as someone else. This is not a probl

      • Re: (Score:2)

        by DrKyle ( 818035 )
        I'm sorry, did you teach this to 4th year genetics students this semester? No? Well, I did teach this for a couple lectures this year, and while I have simplified the process to make it understandable to non-biologists I will assure you I am pretty right on the money.

        The standard CODIS set of 13 microsatellites has been in use since 1997, not really that recent if you ask me.

        Birthday paradox... yes, only 365 possibilities, a good chance of collisions, CODIS database, a quintillion combinations (not coun

        • Re: (Score:1)

          by delt0r ( 999393 )
          No, but i did teach at a workshop on Population genetics. Also i have worked with a group with the courts on the real probablities. Not the made up probablities, but probablities based on real data. Its not straight forward and its far from cut and dry. We are not using SNP's with the groups I work with. But then thats not the US. As for the birthday paradox there are 400 million people in europe. Thats 80x10^15 pairs of people, so to not have a collision p10^-18. In fact it is assumed that the bigger data

    • As has already been commented, it's not necessarilly valid to simply multiply out the individual probabilities as if all the elements were truly independent, since they may not be, and 15^13 is a very big number and an exceedingly bold claim to make. FTFA the chance of a random match between two people is stated as being about 1 in 1 billion, which is roughly what I've seen quoted before for the type of test currently used by the Forensic Science Service.

      Now you throw in the effect of the Birthday Paradox [wikipedia.org],

  • Upping the what now? (Score:3, Interesting)

    by jesdynf ( 42915 ) on Wednesday October 04, 2006 @11:05PM (#16316273) Homepage
    The /crime detection/ rate is up by 15%? Just great. How many headless corpses and savage beatings were we not noticing before this? Are they finally going to start ticketing that bastard who parks in the middle of four spaces in my complex or something?
    • Suppose there are 10 headless corpses each week, and the police can't explain 5 of them. That's a rate of 50%. All they need to do is to issue tickets to 3 bastards who park in the wrong place, and now they've solved 8 crimes out of 13, so the rate is over 60%, which is more than 15% up.

      So yes, I would think that you are probably in luck.
      • Even if the police "can't explain" a particular headless corpse, they still presumably know a crime was committed! Better/faster DNA analysis does *not* improve *detection* of crimes at all, even if it aids *solution* of crimes.
  • the technique is a world first which will boost its crime detection rates by more than 15%

    And when it reaches 100% nobody is safe.

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