Open Menu

Tech

Search
Criminal-convicting crotches

Criminal-convicting crotches

WA research suggests pubic bacteria could betray sex offenders.

Criminal-convicting crotches

Microbiomes are a pretty hot topic.

People are going gaga for good gut bugs and the health benefits they confer.

But did you know your pubic hair hosts an equally useful collection of microbes?

Everyone’s bush bugs are as unique and identifiable as a fingerprint, and now that fingerprint could help catch criminals.

PUBIC PRINTING

Sexual criminals have grown wise over the years, if not less abhorrent.

Increasingly, assaulters have been using condoms. Not only are condoms the best method for preventing STDs, but they also prevent otherwise incriminating DNA from being left at the scene.

But humans swap more than semen and vaginal secretions when we have sex.

Researchers at the Trace and Environmental DNA (TrEnD) lab at Curtin University have discovered that the bacteria on a person’s pubic hair can act as a unique sexual signature and will leave a trace wherever it goes.

HAIR RAISING

Hairs have often featured as evidence in criminal cases. In the past, we could only look at the DNA of a single species—the Homo sapiens who shed said hair.

The hair itself does not actually contain any DNA. The cells in the hair shaft are all dead and keratinised. A hair can only be used for DNA analysis if the root is attached.

Unfortunately, not all hairs dropped at crime scenes carry that condemning collection of cells.

But with advances in DNA sequencing technologies, scientists can look not at the hair but at the microbes that call the hair home.

Our pubic hairs house over 70 different species of bacteria, which are highly personalised. Comparatively, head hairs only house 50 or so species, which are more defined by our environment.

Metagenomic DNA sequencing is allowing researchers to analyse the DNA of all 70 bacteria species that exist on an individual’s pubic hair, and what they tell us could change how we convict sexual criminals.

LOVE BUGS

Over a 5-month period, TrEnD researchers collected samples of pubic hair from research participants. By looking at which bacteria were present, they could consistently and reliably identify whose hair was whose.

That was until one exciting hair-sampling session, when researchers found that two pubic hair samples seemed to share a significant amount of the same bugs.

As it turns out, those two individuals had had sex just 18 hours before. In sharing the love, these two individuals had also shared their pubic hair bacteria.

Prosecuting pubes

In a statement, lead researcher Silvana Tridico said, “The implication of this present study is that the transfer of bacteria between victim and offender, in rape cases, may provide a new way of linking the offender to the victim, in instances in which no human DNA is transferred.”

So even if no visible genetic evidence remains, DNA analyses may still allow us to apprehend an assaulter.

However, the study was a preliminary one, with only seven individuals donating a combined 42 samples of hair over 5 months. Despite initially promising results, more research is required before anyone gets convicted by their pubic hair bacteria.

Particle
Puns

Postcard #8
The science story accelerator
Space was cool…before it mattered

Republish

Creative Commons Logo

Republishing our content

We want our stories to be shared and seen by as many people as possible.

Therefore, unless it says otherwise, copyright on the stories on Particle belongs to Scitech and they are published under a Creative Commons Attribution-NoDerivatives 4.0 International License.

This allows you to republish our articles online or in print for free. You just need to credit us and link to us, and you can’t edit our material or sell it separately.

Using the ‘republish’ button on our website is the easiest way to meet our guidelines.

Guidelines

You cannot edit the article.

When republishing, you have to credit our authors, ideally in the byline. You have to credit Particle with a link back to the original publication on Particle.

If you’re republishing online, you must use our pageview counter, link to us and include links from our story. Our page view counter is a small pixel-ping (invisible to the eye) that allows us to know when our content is republished. It’s a condition of our guidelines that you include our counter. If you use the ‘republish’ then you’ll capture our page counter.

If you’re republishing in print, please email us to let us so we know about it (we get very proud to see our work republished) and you must include the Particle logo next to the credits. Download logo here.

If you wish to republish all our stories, please contact us directly to discuss this opportunity.

Images

Most of the images used on Particle are copyright of the photographer who made them.

It is your responsibility to confirm that you’re licensed to republish images in our articles.

Video

All Particle videos can be accessed through YouTube under the Standard YouTube Licence.

The Standard YouTube licence

  1. This licence is ‘All Rights Reserved’, granting provisions for YouTube to display the content, and YouTube’s visitors to stream the content. This means that the content may be streamed from YouTube but specifically forbids downloading, adaptation, and redistribution, except where otherwise licensed. When uploading your content to YouTube it will automatically use the Standard YouTube licence. You can check this by clicking on Advanced Settings and looking at the dropdown box ‘License and rights ownership’.
  2. When a user is uploading a video he has license options that he can choose from. The first option is “standard YouTube License” which means that you grant the broadcasting rights to YouTube. This essentially means that your video can only be accessed from YouTube for watching purpose and cannot be reproduced or distributed in any other form without your consent.

Contact

For more information about using our content, email us: particle@scitech.org.au

Copy this HTML into your CMS
Press Ctrl+C to copy