Criminals who inadvertently leave traces of their DNA at the crime scene now have something more to worry about. By isolating 24 genetic variants, researchers have developed a computer program that can construct surprisingly accurate 3D models of facial features.
Forensic science is progressing quickly these days owing to a number of breakthroughs. Investigators can use DNA evidence to predict hair and eye color of suspects, use maggots to extract a victim's DNA from their otherwise unrecognizable bodies, detect hidden faces by zooming into hi-res photos of eyes, and use DNA to create virtual mugshot's of a suspect's face.
But unlike previously limited efforts to map human faces using DNA, the new initiative by anthropologist and population geneticist Mark Shriver of Pennsylvania State University has taken the process to the next level. His team managed to isolate the most critical genetic variations required to create accurate facial reconstructions. They did so by using a stereoscopic camera to capture 3D images of almost 600 volunteers of various ancestry.
From New Scientist:
...Claes and Shriver superimposed a mesh of more than 7000 points onto the scanned 3D images and recorded the precise location of each point. They also developed a statistical model to consider how genes, sex and racial ancestry affect the position of these points and therefore the overall shape of the face.
Next the researchers tested each of the volunteers for 76 genetic variants in genes that were already known to cause facial abnormalities when mutated. They reasoned that normal variation in genes that can cause such problems might have a subtle effect on the shape of the face. After using their model to control for the effects of sex and ancestry, they found 24 variants in 20 different genes that seemed to be useful predictors of facial shape.
Check out how the system recreated the face of New Scientist reporter Sara Reardon:
This process is not quite ready for prime time, but with a few more refinements — like running larger studies in different populations to confirm statistically reliability — it could start to make an impact in criminal investigations. It could even be used to reconstruct the faces of long-lost ancestors (even potentially Neanderthals), so long as their DNA is intact (or artificially reconstructed).
Read more at New Scientist. And check out the entire study for free at PLoS Genetics: "Modeling 3D Facial Shape from DNA."