Identikit pictures of criminals could soon be as easy as DNA

SCIENCE is on the verge of being able to show police what murderers, rapists and other criminals actually look like from DNA they leave at the scene.

Angela van Daal, a biomedical and forensics expert from Queensland's Bond University, says it might take as little as five years before her breakthrough research becomes crime-fighting reality.

Her work could give investigators the ability to create an identikit picture of an offender, without the help of witnesses.

Dr van Daal said she had already been able to link a series of genetic markers to complex human characteristics such as height, skin, eye and hair colouring and some facial features.

Further research is expected to be able to show how far apart someone's eyes are set, whether they have a large or small nose and the general shape of their cheekbones.

"What I want to be able to do is take DNA from a crime scene and predict, with some degree of confidence, what the person who left the sample may look like," she said.

"It's in the area of colouring where we've been making most progress, I guess - we don't have the complete picture and that will be a while, but we certainly have some information to work with."

Two major scientific developments make the groundbreaking work possible: the decade-long US Human Genome Project to identify all 25,000 genes found in human DNA and the capacity to replicate DNA strands from the most minuscule fragments of hair, blood, skin, saliva and semen.

Successful samples are even being collected from oils secreted through hands and other parts of the body that brush or rub against objects at a crime scene.

Dr van Daal said the only possible limitations were the environmental factors that contributed to the way a person looked.

"Obviously some people are naturally thin, but work hard at not being so because they put a lot of junk food in their mouths," she said.

"Those things we will simply not be able to predict in the same way. We might be able to say what's likely but that's not going to take into account their diet. Obviously, a person can also alter their hair colour."

Dr van Daal said there was potential for her work to apply to cold-case crimes where useable DNA samples were kept.

NSW Police Forensic Services Director Carlene York is surprised at the claim that suspect identikits would be based on DNA so soon.

"While the community sometimes worries about what we do with DNA, it's obviously something that could be very useful to us," Assistant Commissioner York said.

"Providing the appropriate protocols and processes were put in place, as an intelligence tool, it's potentially terrific."