Today scientists are using genetic markers from DNA to build up a picture of an offender’s face, a process known as molecular photo fitting.
A DNA profile is only useful to detectives if a match can be found on a database.
As surgeon Gabriel Weston explains in the BBC series Catching History’s Criminals: The Forensics Story, this technology offers the tantalising prospect of generating a face from nothing more than a few cells.
To find out just how effective this process can be, DNA was extracted from Gabriel’s saliva and the results sent anonymously to a group of scientists in Belgium.
From that data they set about building a picture of Gabriel’s face – as predicted by her genes. The question was: Would it look anything like her?
The job of turning the cells in her saliva into a picture of her face was carried out by Dr Peter Claes, a medical imaging specialist at the University of Leuven.
Along with colleagues in the US, he’s built up a database of faces and DNA. And armed with this information, he’s able to model how a face is constructed based on just 20 genes.
It is possible to judge just how much the picture of Gabriel’s face – based on her genetic makeup – looks like her by comparing it to her actual image.