Scientists can now identify criminals using a single strand of hair

It wasn’t long ago that we talked about how examining human hair might help us to diagnose schizophrenia, a little-understood mental illness that we’re only now beginning to learn more about. Now news reveals that hair doesn’t just have its uses in the medical world – it’s also being used in police forensics, and has proved incredibly beneficial.

As reported in sciencemag.org, a very precise new forensic method has been created which may be able to use a single strand of hair to identify a person. The reason why this new method is so exciting? Well, previously, to get reliable data from hair, forensic scientists would also need DNA from skin still attached to the hair follicles. But thanks to a recent technological advancement, we can now look purely at the proteins in the hair itself, such as keratin.

Scientists know that the sequences of amino acids in hair proteins is different for each person, depending on their own genetic coding. With this information, we should be able to now identify people far more accurately without necessarily needing DNA.

Researchers think that all they’ll need is less than a centimetre of a single strand of hair to be able to carry out a positive analysis, which is an impressive eight times more sensitive than other protein analysis techniques that currently exist. Just imagine how the new method could assist in getting justice – it would make it far, far easier to correctly identify the people who were at the scene of a crime.

Sadly, the new method still isn’t as developed as perhaps it will be one day. Most researchers who have tried out the method have gone through a process of grinding and heating the hair to capture the relevant proteins, which, ironically, can destroy much of the protein in turn. And then there’s the problem with variation – or not enough of it. Sometimes, scientists might not be able to confidently analyse a person based on the proteins they’ve uncovered.

However, there is hope that we might be able to more successfully extract proteins from the hair one day. Scientists at the National Institute of Standards and Technology, again, reported on by sciencemag.org, discovered a way of carrying out the method by only heating the hair in a detergent mix, which they found to recover more proteins than when grinding was used. It’s certainly a step in the right direction.

So, what does this mean for the future of fighting crime? Well, at the moment, hair doesn’t have the best name for itself in the world of forensics, and many people have previously been convicted in the courtroom who have later been found to be innocent. This is because in the past, hair forensics relied on very basic factors, such as the thickness and colour of a strand of hair, to deem a person guilty. Imagine if you’d been in the wrong place at the wrong time, and just happened to have the same hair colour and texture as a criminal? Far from ideal.

Hopefully, this new method will drastically improve accuracy, as we all have different protein structures in our hair. Keratin, which is the protein that makes up our hair, has a number of different amino acids, and while we all have the same number of amino acids in our hair strands, the ratios will vary from one person to another.

Ingeniously, examining just a single strand of hair may lead a scientist to discover a person’s age, race, body mass index and their place of origin. Even if a criminal can’t be all-out identified by a scientist, it definitely gives them plenty of important information about the person’s physical characteristics.

It’s going to be very interesting to see how exactly this new method of hair forensics will be used in future – or, indeed, past – crime cases. This new opportunity to learn more about criminals who may be unidentified or on the run might help police detectives to solve cases that have so far remained a mystery.

We might take our hair for granted on a daily basis – it’s one of our features that most of us won’t think much about. And why would we? It’s not helping us directly. But perhaps future criminals might want to think about shaving their heads pretty soon if they want to try and evade the police for good…

(Image credit: globalnews)