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The DNA Connection: Is DNA a Silver Bullet?

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  • gmgodwin
    The DNA Connection: Is DNA a Silver Bullet? By: Chris Asplen Issue: June/July 2009 Every now and then, although much less recently, a reporter asks me the
    Message 1 of 4 , Jul 7, 2009
      The DNA Connection: Is DNA a Silver Bullet?
      By: Chris Asplen
      Issue: June/July 2009


      Every now and then, although much less recently, a reporter asks me the
      inane question, "Is DNA a silver bullet?"While the obvious
      answer is "no," the follow-up is always, "DNA will never
      replace a thoughtful, creative detective with the proper
      resources."No one has ever disagreed with me on that. That is
      however, the positive spin on the answer. Another approach is,
      "Regardless of how good the technology is, it is ultimately a system
      run by human beings—mistakes can and will be made." Does the
      case of a certain Heisman trophy winner come to mind?

      Last fall, the British newspaper The Guardian ran a lengthy article on
      the most significant serial killer in Europe. The killer, dubbed
      "the woman without a face" was implicated in six murders,
      including the murder of a female German police officer shot in the back
      of the head while she sat in her patrol car. The killer was not just a
      brutal executioner though, she was a thief (DNA was found at numerous
      burglary scenes) and a drug addict (DNA was found on a heroin syringe).
      She was a frequent traveler, her DNA being found at crime scenes in
      Germany, Austria, and France. And her weapon of choice varied (DNA was
      found on a stone used to smash a victim's face).

      The "woman without a face" was law enforcement's worst
      nightmare—elusive, seemingly indiscriminant, violent, and well
      traveled. DNA samples were taken from3,000 homeless women believed to be
      drug users. A reward of €100,000 ($135,000) was posted. And German,
      Austrian, and French authorities spent millions of Euros on the
      investigation.

      In the course of the story, the reporter interviewed a prosecutor (note
      this isn't just about the police) in charge of the investigation.
      When talking about the status of the unsolved case, the prosecutor said,
      "There are still no witnesses, and no other evidence. All of us on
      the various teams talk to each other two or three times a month. We
      meet, we email, but mostly we wait for another report saying the same
      DNA has turned up."

      Uh-oh. That's a bad statement.

      There is too much art in criminal investigation to call it a scientific
      endeavor. At the same time, we rely too much on science now to ignore
      the scientific method that requires us to always question our
      assumptions. If we are waiting "for another report saying the same
      DNA has turned up," we have lost sight of our need to rigorously
      apply the scientific method to the context of our criminal
      investigations.

      As it turns out, our serial killer, our female executioner without a
      face, is really a 71-year-old woman armed with cotton swabs and a poor
      protocol for avoiding contamination. Police announced in March that they
      had determined cotton swabs were contaminated with the DNA of the woman
      packaging them. The tip off? Police were attempting to identify the body
      of a burn victim they believed to be an asylum seeker. They found the
      victim's application for asylum and swabbed the fingerprints it
      contained. The DNA analysis yielded the profile of the notorious serial
      killer. There was only one problem—the body they were seeking to
      identify, and to whom the fingerprints belonged, was male. Swabbing the
      prints again with a different swab kit, the analysis yielded a different
      profile, and appropriately, the profile of a male. Thus began an
      embarrassing exercise in hindsight.

      Let's start with the basics. Female serial killers like this are
      rare. Serial killers with this diversity of crimes are rare: police
      executioner, common thief, and school burglar. Some of the crimes were
      committed with "accomplices" who were convicted of those crimes
      but who denied the existence of a female cohort. There was no connection
      between the criminals she allegedly commited her various and diverse
      crimes with. Throughout this entire crime spree, no one had ever seen
      her. And in those instances where the vaguest of descriptions could be
      given, it was of someone who looked like a man. And that rock used to
      smash a victim's face? No blood, no tissue, just the
      "perpetrator's" DNA.

      To be clear, the Europeans are no slouches at using DNA to solve crime.
      This is just one reminder, one lesson in a long line of examples, that
      compels all of us to be more rigorous in questioning our investigative
      assumptions. As bad as the wasted money is, as embarrassing as the
      failures are, they pale in seriousness and severity to the realization
      that "over reliance" on DNA—and a failure to question more
      and assume less—means that several killers remain on the loose.

      http://www.forensicmag.com/articles.asp?pid=278
      <http://www.forensicmag.com/articles.asp?pid=278>



      [Non-text portions of this message have been removed]
    • nonarevers
      Still in the news , usually referred to as the Phantom of Heilbronn http://www.welt.de/die-welt/article4079607/Welt.html 8. Juli 2009, 04:00 Uhr After the
      Message 2 of 4 , Jul 8, 2009
        Still in the news , usually referred to as the Phantom of Heilbronn
        http://www.welt.de/die-welt/article4079607/Welt.html
        8. Juli 2009, 04:00 Uhr

        After the serious breakdown in the police investigation into the murder of Heilbronn have police experts on new standards for the use of cotton swabs and gloves to track security agreement. Accordingly to sample DNA traces only with cotton swabs to secure a manufacturer whose products are sterilized with ethylene oxide, such as the Baden-Württemberg Ministry of the Interior announced on Tuesday in Stuttgart. According to current knowledge, this is the best method to eliminate impurities. Also check on a regular basis the quality of the cotton swab with so-called `Leerprobenuntersuchungen`
        End of approx translation

        Could someone put me straight? I'm not a biochemist.
        This whole farce was because of the use of cotton, a natural product requiring much human handling, not a plastics based material. Ethylene oxide will not destroy any DNA contamination. Are they still confusing sterile with DNA-free ? Imagine if they used touch DNA/ LCN

        closer source story , in English
        http://www.spiegel.de/international/germany/0,1518,615608,00.html


        ps
        What they aren't telling you about DNA profiles
        and what Special Branch don't want you to know.
        http://www.nutteing.chat.ru/dnapr.htm
        or nutteingd in a search engine.

        --- In forensic-science@yahoogroups.com, "gmgodwin" <gmgodwin@...> wrote:
        >
        > The DNA Connection: Is DNA a Silver Bullet?
        > By: Chris Asplen
        > Issue: June/July 2009
        >
        >
        > Every now and then, although much less recently, a reporter asks me the
        > inane question, "Is DNA a silver bullet?"While the obvious
        > answer is "no," the follow-up is always, "DNA will never
        > replace a thoughtful, creative detective with the proper
        > resources."No one has ever disagreed with me on that. That is
        > however, the positive spin on the answer. Another approach is,
        > "Regardless of how good the technology is, it is ultimately a system
        > run by human beings—mistakes can and will be made." Does the
        > case of a certain Heisman trophy winner come to mind?
        >
        > Last fall, the British newspaper The Guardian ran a lengthy article on
        > the most significant serial killer in Europe. The killer, dubbed
        > "the woman without a face" was implicated in six murders,
        > including the murder of a female German police officer shot in the back
        > of the head while she sat in her patrol car. The killer was not just a
        > brutal executioner though, she was a thief (DNA was found at numerous
        > burglary scenes) and a drug addict (DNA was found on a heroin syringe).
        > She was a frequent traveler, her DNA being found at crime scenes in
        > Germany, Austria, and France. And her weapon of choice varied (DNA was
        > found on a stone used to smash a victim's face).
        >
        > The "woman without a face" was law enforcement's worst
        > nightmare—elusive, seemingly indiscriminant, violent, and well
        > traveled. DNA samples were taken from3,000 homeless women believed to be
        > drug users. A reward of €100,000 ($135,000) was posted. And German,
        > Austrian, and French authorities spent millions of Euros on the
        > investigation.
        >
        > In the course of the story, the reporter interviewed a prosecutor (note
        > this isn't just about the police) in charge of the investigation.
        > When talking about the status of the unsolved case, the prosecutor said,
        > "There are still no witnesses, and no other evidence. All of us on
        > the various teams talk to each other two or three times a month. We
        > meet, we email, but mostly we wait for another report saying the same
        > DNA has turned up."
        >
        > Uh-oh. That's a bad statement.
        >
        > There is too much art in criminal investigation to call it a scientific
        > endeavor. At the same time, we rely too much on science now to ignore
        > the scientific method that requires us to always question our
        > assumptions. If we are waiting "for another report saying the same
        > DNA has turned up," we have lost sight of our need to rigorously
        > apply the scientific method to the context of our criminal
        > investigations.
        >
        > As it turns out, our serial killer, our female executioner without a
        > face, is really a 71-year-old woman armed with cotton swabs and a poor
        > protocol for avoiding contamination. Police announced in March that they
        > had determined cotton swabs were contaminated with the DNA of the woman
        > packaging them. The tip off? Police were attempting to identify the body
        > of a burn victim they believed to be an asylum seeker. They found the
        > victim's application for asylum and swabbed the fingerprints it
        > contained. The DNA analysis yielded the profile of the notorious serial
        > killer. There was only one problem—the body they were seeking to
        > identify, and to whom the fingerprints belonged, was male. Swabbing the
        > prints again with a different swab kit, the analysis yielded a different
        > profile, and appropriately, the profile of a male. Thus began an
        > embarrassing exercise in hindsight.
        >
        > Let's start with the basics. Female serial killers like this are
        > rare. Serial killers with this diversity of crimes are rare: police
        > executioner, common thief, and school burglar. Some of the crimes were
        > committed with "accomplices" who were convicted of those crimes
        > but who denied the existence of a female cohort. There was no connection
        > between the criminals she allegedly commited her various and diverse
        > crimes with. Throughout this entire crime spree, no one had ever seen
        > her. And in those instances where the vaguest of descriptions could be
        > given, it was of someone who looked like a man. And that rock used to
        > smash a victim's face? No blood, no tissue, just the
        > "perpetrator's" DNA.
        >
        > To be clear, the Europeans are no slouches at using DNA to solve crime.
        > This is just one reminder, one lesson in a long line of examples, that
        > compels all of us to be more rigorous in questioning our investigative
        > assumptions. As bad as the wasted money is, as embarrassing as the
        > failures are, they pale in seriousness and severity to the realization
        > that "over reliance" on DNA—and a failure to question more
        > and assume less—means that several killers remain on the loose.
        >
        > http://www.forensicmag.com/articles.asp?pid=278
        > <http://www.forensicmag.com/articles.asp?pid=278>
        >
        >
        >
        > [Non-text portions of this message have been removed]
        >
      • nonarevers
        I d not seen that English newspaper coverage http://www.guardian.co.uk/lifeandstyle/2008/nov/09/germany-serial-killer 2008 nov 09 Not actually the Guardian
        Message 3 of 4 , Jul 8, 2009
          I'd not seen that English newspaper coverage
          http://www.guardian.co.uk/lifeandstyle/2008/nov/09/germany-serial-killer
          2008 nov 09
          Not actually the Guardian newspaper but assuming
          the rest of his reportage is corrct
          ("boyish-looking 44-year-old prosecutor" etc) it gives a fascinating
          insight into the prosecutorial psychological mindset.
          Instead of 15 years of serial forensic scientists'
          incompetence (where were the control null results ?) we get

          "If their Iraqi suspect can help, police say, he's not telling."

          " At least three men have been arrested - from Slovakia, Serbia and Moldova. But again, if they know anything about the Phantom of Heilbronn, they're not saying."

          "The syringe suggests drug use. The apparent randomness of the break-ins, the small amounts often taken, point to targets of opportunity and a desperate need for cash."

          " the bullet used in the gypsy feud in Worms have convinced the police that she may have ties with one of the loosely linked groups and communities who move back and forth across Europe's increasingly porous frontiers."

          "she may be part of an 'organised group of burglars from Eastern Europe'. But a colleague quickly interrupts: 'Even in jail, these people don't talk.'"

          "'There are lots of people and communities who move around,' he says, before adding that the real problem - his real frustration - is that there are other, more serious limitations to the almost magical power now sometimes attributed to DNA. He points to rumours in Austria, where limits on DNA testing are less stringent, suggesting that she may have blonde hair and blue eyes."

          This reporter bit is worthy of the Express (another UK newspaper)
          "Horn is particularly quick to bat away suggestions raised in the wake of the Heilbronn killing, which was not far from a gypsy community, and the clan shooting in Worms, that the mystery woman may have ties to the gypsy, or Romany, community, which was targeted during the Holocaust, alongside the similarly 'non-Aryan' Jews."



          ps
          What they aren't telling you about DNA profiles
          and what Special Branch don't want you to know.
          http://www.nutteing.chat.ru/dnapr.htm
          or nutteingd in a search engine.
        • nonarevers
          Answering myself, Ethylene Oxide does seem to destroy DNA enough for standard PCR purposes, but not incontrovertably , eg not to LCN levels International
          Message 4 of 4 , Jul 9, 2009
            Answering myself, Ethylene Oxide does seem to destroy DNA enough for standard PCR purposes, but not incontrovertably , eg not to LCN levels

            International Journal of Legal Medicine
            Issue Volume 122, Number 1 / January, 2008
            http://www.springerlink.com/content/y234786488g68273/?p=363698ff7a65437f84cfa9c508e02b97&pi=4

            Comparison of the effects of sterilisation techniques on subsequent DNA profiling

            Abstract It is important that contamination from extraneous DNA should be minimised on items used at crime scenes and when dealing with exhibits within the laboratory. Four sterilisation techniques (UV, gamma and beta radiation and ethylene oxide treatment) were examined for their potential to degrade contaminating DNA to such an extent that subsequent DNA profiling was impossible. This work indicated that the most successful technique to reduce DNA contamination was ethylene oxide treatment. Of the radiation techniques tested in this study, gamma was the most successful at eradicating DNA and UV radiation was the least. None of the contaminated samples treated with ethylene oxide and subsequently subjected to DNA analysis met the DNA profile criteria necessary for acceptance on the UK National DNA Database. Contaminated cotton swabs and micro-centrifuge tubes treated with ethylene oxide showed a marked decrease in amplifiable DNA post-treatment. Ethylene oxide treatment to sterile swabs and tubes did not significantly affect subsequent DNA analysis.

            ps
            What they aren't telling you about DNA profiles
            and what Special Branch don't want you to know.
            http://www.nutteing.chat.ru/dnapr.htm
            or nutteingd in a search engine.
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