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Science Technology

Scientists Can Now Identify Someone From a Single Strand of Hair (sciencemag.org) 76

Posted by BeauHD from the ultra-sensitive dept.
sciencehabit shares a report from Science Magazine: A new forensic technique could have criminals -- and some prosecutors -- tearing their hair out: Researchers have developed a method they say can identify a person from as little as 1 centimeter of a single strand of hair -- and that is eight times more sensitive than similar protein analysis techniques. If the new method ever makes it into the courtroom, it could greatly expand the ability to identify the people at the scene of a crime. To get reliable data from hair, forensic scientists previously needed DNA from skin still attached to hair follicles. But recent technologies have instead analyzed proteins in the hair itself, like keratin. Because the sequences of amino acids in proteins vary slightly from person to person based on their genetic code, this information can be used to identify people with a high degree of accuracy without DNA.

The catch? Most methods require several steps of grinding and heating the hair, which destroys much of the protein. And scientists might not always detect enough variation in the remaining proteins to make a confident identification. To get more proteins for analysis, scientists at the National Institute of Standards and Technology (NIST) did away with the grinding and developed a method with only one step: heating the hair in detergent solution. When the researchers used mass spectrometry analysis to find out what they had extracted from the dissolved hair, they found they recovered more proteins -- and their subunits, peptides -- than with other extraction techniques. They also identified a dozen new protein building blocks called genetically variant peptides (GVPs) that differ among individuals. These new GVPs join thousands of others in NIST's library of peptide sequences. GPVs aren't yet used to identify people in criminal cases -- but could be in the future. There are still some drawbacks with this new method. "To get enough material to build a profile, scientists need 1 day or more, as well as extensive experience with sophisticated protein analysis techniques," the report says.

"In addition, no identification method based on genetically variant peptides in hair proteins has been used in court. There are still a lot of questions to be answered before that's a reality."
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Scientists Can Now Identify Someone From a Single Strand of Hair More

Scientists Can Now Identify Someone From a Single Strand of Hair

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  • Or at least do it -before- your hair cut.

  • I remember they made a movie about that where they identified a killer when they found a single strand of hair in an astronaut training facility.

    • Are you talking about Gattaca?

      • No...I can't remember the name, but it had Uma Thurman in it

        • That was, indeed, Gattaca
          https://en.wikipedia.org/wiki/... [wikipedia.org]
          Which was a very good movie.... at least for its time.

          • No, it didn't look like that one. It was a pretty old movie. It was all about DNA analysis in the future.

            • That's Gattaca! Genetics, space, late 90's, about the future, Jude Law, Uma Thurman.... I have watched it probably at least 5 times.

              • Nah, this movie had Ethan Hawke in it, not Jude Law. You are probably thinking of the movie "A.I."

                • You are being obtuse! Gattaca had Ethan Hawke AND Jude Law.

                  But A.I- yes, I do love that movie, too. Very good.

                  • No, I remember now. It was called "GATTACA". The title was a play on the DNA alphabet. G=guanine, C=cytosine, A=adenine and T=thymine. If you combine the letters you get the title.

                    • Lol omg you're fucking hilarious! Thank you!

                    • I never made that connection. Thank you for the insight. I think the go to answer is now going to be .

                      This test will only prove that your body was there at some point in time. At no point in time does it prove how meticulous the cleaning crew is. I mean if you lost an eyelash or a hair from your eyebrow, there is really no way to prove if that shit has been there months or years. It will certainly be difficult to prove beyond a reasonable doubt. I already have reasonable doubt that that test is going to sho

                    • Oh god I'm in tears! That was a funny exchange. Well played.

                    • One day you're going to fuck up and use the wrong sock puppet account.

                    • This is my on,y account. No idea who else you think I am. I've been here posting as AC since when /. was new and only got this account when AC were banned from posting. What exactly should I be afraid of? You're being ridiculous and dramatic.

                    • >"Oh god I'm in tears! That was a funny exchange. Well played." :) I make the perfect "straight man" in such jokes.

              • I remember that movie. It was about cars but there was also some technobabble which you could easily skip over.

  • exoneration (Score:5, Insightful)

    by Jodka ( 520060 ) on Thursday November 21, 2019 @10:20PM (#59441288)

    from the linked article:
    "Protein sequences are highly individual, but there’s still a chance—one in 1 million or even one in 10 million—that two people share the same one."

    So the false positive rate is 0.0001%. In conjunction with other evidence, such as geographical proximity, that's useful.

    But the false negative rate is zero. So maybe it's a tool to exonerate the falsely accused. Except for that "We found this hair at the scene of the crime which is not yours, so we know you are innocent" does not really work.

    • Even this is a little misleading. Because they only test a small set of markers the risk of a match is even greater.

      "But the false negative rate is zero. So maybe it's a tool to exonerate the falsely accused. Except for that "We found this hair at the scene of the crime which is not yours, so we know you are innocent" does not really work."

      This is apples and oranges logic. Not finding someones hair at the scene of a crime is definitely exonerating and does really work, because otherwise you are then refus

      • > you should never ever work from the logic that someone who failed to prove they are innocent might be guilty... it absolutely must always be innocent until someone proves guilt.

        Yes, that's true. Just to simplify things, let's acknowledge the extreme case - there is no evidence. If there is no evidence, you would find the person not guilty.

        It's ALSO true that if the perpetrator left their shirt at the scene of of the crime, that would be evidence. If they did not leave their shirt, that's not evidence

        • > Yes, that's true. Just to simplify things, let's acknowledge the extreme case - there is no evidence. If there is no evidence, you would find the person not guilty.

          Or the police would lie about the "DNA evidence" to get someone to sign a plea agreement. And the chain of custody for a single hair is much less reliable than that for a blood stained garment. I'd expect to see some cases of planted evidence occurring very soon.

      • Re:exoneration (Score:5, Insightful)

        by ShanghaiBill ( 739463 ) on Friday November 22, 2019 @12:44AM (#59441536)

        it absolutely must always be innocent until someone proves guilt.

        Or until the defendant runs out of money to fund his defense and has to accept a plea deal.

        In Federal court, a proper defense can cost $100k or more. Most defendants can't afford that especially if they are innocent. So 95% plead guilty. As part of the plea deal, defendants are almost always required to give up their right to appeal, so even new exonerating evidence can't help them.

        Innocence is irrelevant in the age of the plea bargin [theatlantic.com].

        Your belief in the fairness and impartiality of the justice system is similar to believing in Santa Claus.

        • $100k is chump change. Unless the case is so obviously bogus that the lawyer can get it thrown out right away, that money is going to be gone pretty quickly when you consider that a good lawyer can cost more than $500 per hour. So that $100,000 is really only 200 hours of work and that adds up a lot quicker than most people expect.

          That isn't the real problem though since merely being accused is going to destroy your reputation completely and no one really cares about or reads the retractions buried on pa

    • Re: (Score:3)

      by sjames ( 1099 )

      You may never hear it in court, but one of your hairs found at the scene of the murder means either you were there sometime in your life (possibly years prior) or someone who bumped in to you was there at some point. It's even quite possible that someone who bumped in to someone who bumped in to you was there.

      • Oh dear God please tell me were are not resurrecting the 6 Degrees of separation from Kevin Bacon game.

        • Re: (Score:2)

          by sjames ( 1099 )

          Don't worry, detectives and prosecutors will happily translate it into hair there == incontrovertibly guilty. They'll have 'expert witnesses' who will happing claim that there is absolutely no other way one of your hairs could have ended up in the same room as the corpse.

    • It doesn't have to prove guilt to be useful to law enforcement. Even IF courts only allow DNA to directly prove INNOCENCE, it's still a source of potential (and not necessarily obvious) leads to investigate. And judges WILL probably show increased willingness to allow it to justify search warrants to look for evidence that CAN be used in trial.

      • If weâ(TM)re talking about a public place, simply state you vaguely remember being there once or twice in the last couple years but nothing recent.

    • Re: (Score:3)

      by AmiMoJo ( 196126 )

      You should look at how this kind of forensic evidence is actually used in court.

      With previous DNA evidence trials have collapsed because of misuse. The police find something, tie it to one person's DNA and arrest them. In court the defence points out that with a 1 in 1,000,000 chance of a mismatch there are 65 other people in the country that also match, and it becomes circumstantial evidence at best. If the police didn't also investigate the other 65 people it makes them look sloppy and like they decided t

      • yes, for decades juries have been given evidence like "witnesses saw a red car drive away, and the defendant has a red car"

  • So you could potentially interact with a murderer weeks before the crime, transfer a minuscule bit of hair to them, and then have your hair found at the murder scene. Or what if the murder occurred at a location you visited week before? Or you interacted with the victim long before the crime. Then they will use your hair as evidence you were involved?
  • We just can't narrow it down any farther.

  • at scene (Score:5, Insightful)

    by markdavis ( 642305 ) on Thursday November 21, 2019 @10:26PM (#59441300)

    >"it could greatly expand the ability to identify the people at the scene of a crime."

    No, it could greatly expand the ability to identify a HAIR was at the scene of the crime.

    1) It could have blown there from far away.
    2) It could have been from months or even years ago.
    3) It could have traveled there on someone's clothing or shoes before or after the event.
    4) It could have been planted there.

    Which is the problem with most such "evidence." Doesn't prove they were there, doesn't say anything about opportunity, nor motive. Handled incorrectly, it can be extremely prejudicial.

    • exactly what my thoughts were. hair can come from all over the place, the earth is not a closed loop environment. hair could blow into a crime scene after caution tape from someone simply walking by.

      • In the future only bald people will be free from suspicion.

        • Well, at the rate I am losing my hair, I guess I will be safe...

        • Eyelashes fall out at random times.
          Nose hairs
          Ear hairs
          Arm hairs...body hairs
          yes, even pubic hairs fall out and get out from clothing on occasion.

          Humans are quite dirty animals; most the dust in your house is your skin cells...
          You'd be better off giving away gifts made from your hair... and touching everything... making sure you have dandruff.... so you contaminate everywhere you can ahead of time. better yet, figure out how to clone and grow your hair and sell human-hair wigs at a loss...

          • Re:Chemo.... bald is not enough (Score:5, Insightful)

            by ShanghaiBill ( 739463 ) on Friday November 22, 2019 @12:55AM (#59441562)

            There is a great business opportunity here.

            You could collect hair from barbershops, cut them into fragments, mix them all together, put a handful into Ziploc bags and sell them on eBay.

            Potential killers could buy bags of random hair fragments and sprinkle them all over the crime scene.

            I wonder if I can get VC funding for this.

    • Sigh. I bet you are one of those rocket surgeons who thinks Hans Reiser was innocent and who thinks "circumstantial evidence" is synonymous with "bad evidence".

      This isn't hard to understand. They won't convict you because they found your hair. They will convict you because, for example, you had a motive, a clear opportunity, you mysteriously disappeared from a brunch an hour before the murder and threw away a shirt (or, say, a fucking car seat) immediately afterwards, _and_ they found your hair at the murd

    • Re: (Score:2)

      by sjames ( 1099 )

      Exactly this! Way too much is made of trace evidence.

    • About the only use I can see for this is giving the cops a list of people to question. And when somebody says they have never been there they confront them with DNA evidence. You and I are smart enough to understand what this means. Your average idiot gangbanger will probably start changing his lie and then they will just keep using his changing story against him to trap him In a series of lies. The sad part is that some of these people are so dumb that they have actually convinced themselves that they have

    • Agree with all of those points, and I think the power of this is a bit overstated, although the raw analytical capability is pretty cool. I think realistically this evidence would have to be taken in conjunction with other evidence from a crime scene.

      But isn't the same true of normal dna evidence? My (possibly mistaken) impression is that just having your dna at the crime scene isn't enough for guilt unless it's found in a way or in a form that is damning. E.g. under victims fingernails, or as blood on a m

      • Yes, it should be just a factor, like all other factors. And any proper trial should frame that "evidence" as what it really is. But it is much weaker than fingerprints and I just worry that too much weight would be placed on very circumstantial evidence.

        The main point of posting was the presumption made in the summary was a perfect example. It does *NOT* prove the person was there.

    • Re: (Score:2)

      by dryeo ( 100693 )

      But it might be enough to convince some poor smuck who can't afford a lawyer to plea bargain to avoid the death penalty, which will look good on the DA's resume next election.

  • Sorry Science, I would have been more impressed if moves and TV shows like CSI had not convinced me you could do that already.

    It's like heck, you need a WHOLE strand of hair? Get with the times Science!

  • I can identify someone with a simple sheet of plastic like a drivers license or library card.

    I'll be impressed when you can zoom & enhance a shitty security video and see the DNA.

  • If this works out, I'm going to get very rich by opening a hair salon. I'll make a few bucks by being a decent barber and developing a large clientele. Most of my money, though, will come from loyal customers who only drop by infrequently, and never, ever for a hair cut.

  • Quick -- burn the evidence (Score:5, Informative)

    by aberglas ( 991072 ) on Friday November 22, 2019 @12:46AM (#59441540)

    When DNA identification came out it started to prove many people innocent (half the people on death row in Illinois, I think).

    So many US southern jurisdiction dealt with the problem by quickly destroying evidence that could be DNA tested.

    If this works, it is likely to have a similar effect. Better destroy evidence now, just in case.

    • https://www.innocenceproject.o... [innocenceproject.org]

    • The Innocence project cleared the names of a whole lot of wrongly accused men. An embarrassingly large number of them had been imprisoned due to false rape accusations. Food for thought.

    • Lets call it for what it is. Its not Illinois. Its Chicago and the surrounding area. The only chance of getting reelected in that city for being a district attorney is to prove high conviction rates. That city has rampant crime because their ridiculous policies are a complete failure. The citizens being idiots that they are, blame the police and the District Attorneyâ(TM)s Office instead of themselves, since they were the morons that elected and voted for these ridiculous policies to begin with. Combi

    • When DNA identification came out it started to prove many people innocent (half the people on death row in Illinois, I think).

      So many US southern jurisdiction dealt with the problem by quickly destroying evidence that could be DNA tested.

      If this works, it is likely to have a similar effect. Better destroy evidence now, just in case.

      Wha? It's more likely to be used to wrongly convict people. Everyone sheds hair all the time and it gets everywhere.

  • I can do that too (Score:3)

    by tinkerton ( 199273 ) on Friday November 22, 2019 @04:50AM (#59441988)

    I just pull on the hair and the person saying 'OW!' is the owner. It doesn't always work though.

  • Do this test: Go have them identify someone from his hair a dozen times. Like send a dozen of your hairs to 23andme.
    And you get up to a dozen differnet answers.

    Yes, it "works" ...Riiight ... Except all the "corner cases", like chimeras (which you already are, if you got a blood transfusion or organ transplant or hair extension), and imperfections of the practical process not expected in the theory (like the fact that they don't sequence the gene whole, but replicate it a million times blend them into tiny

  • This procedure recently identified Donald Trump as a circa 1985 orange shag carpet. I think that's actually pretty close.

    • His DNA is too watered down for an accurate test. But you donâ(TM)t need to use a test to discover that. I have not seen genetics fair so poorly on a person since the days of prince Charles. I mean look at that guy, itâ(TM)s like someone in the royal family knew someone in the royal family if you get my drift.

      Don and Don Junior suffer the same fate. Thank God his daughters got their momâ(TM)s good looks.

  • The problem is too much of this hyped up "science" makes it into the court room. People haven't a clue from science and reality from what they watch on TV. Remember "Touch DNA" which every TV cop show has to use? Well, it's been disproved to be reliable. Just follow the money and power and you'll follow the game.
  • Hasn't this always been an option with DNS sequencing and mitochondrial DNA analysis?

  • Not as in "Wow!", but as in "No way!".

    While it may be true that it is possible to say that person A's genes would produce hair proteins of that sequence, there is no evidence that unidentified persons AAA through ZZZ's DNA would not produce the same proteins. There is not enough of a data set either in the number of peptide variations that would produce functional hair nor in the number and distribution of the DNA that will produce them for a definitive match.

    If I'm on a jury, the prosecution would need mu

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