Molecular eyewitness: DNA gets a human face

From Saturday's Globe and Mail

Canadian police have been quietly using a controversial new genetic technology to reveal the racial background and physical appearance of criminals they are hunting, according to the Florida company that sells the test.

Officials with DNAPrint Genomics, a biotech firm in Sarasota that has offered the test since 2002, say four separate forces in Canada -- including the RCMP -- have used the technology to narrow their search for suspects. This spring, two Canadian investigators made the unusual move of hand-delivering a crime-scene DNA sample to the Florida lab.

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Unlike the more familiar forensic test that tries to match DNA found at a crime scene with samples from known suspects, this test is based on a single recovered sample and has the potential to tell police if the offender they are looking for is white, black, Asian, native, or of mixed race. The company then supplies photos of people with similar genetic profiles to help complete the portrait.

The company says the so-called DNAWitness test has been used in 80 criminal investigations by law-enforcement organizations worldwide, including the U.S. Federal Bureau of Investigation, the U.S. Army and Scotland Yard.

"This could be helpful in solving crimes, more helpful than human eyewitnesses," said Anthony Frudakis, the company's chief scientific officer.

"Our technology serves as a potential molecular eyewitness. It's objective."

It's also advancing at a dizzying pace. This spring, the company launched a new DNA test that can discern a person's eye colour with 92-per-cent accuracy. Meanwhile, the prospect of learning other physical -- even psychological -- traits could soon follow.

But while law enforcers seem to be embracing the new science, it has received a chilly reception from others who compare the technology -- a similar version of which has been developed in Britain -- to racial profiling in the genomics age.

"You still have to make a leap that what you're getting from the DNA correlates to visual characteristics," said Mildred Cho, associate director of the Stanford Center for Biomedical Ethics in California. "Then in order to round those people up, you have to say to the police department, or the force, 'Go find people who look like this, someone who looks black, or someone who looks half black and half Asian.

"This technology really overstates the ability to classify people by race and ethnicity."

For this reason, as well as the risk of tipping off criminals who could try to alter their appearance, Dr. Frudakis said police are loath to discuss their use of the technology -- which appears to be the case in Canada.

Officials at DNAPrint, who sign confidentiality agreements with police, say they cannot reveal details of the Canadian cases and investigators they contacted on behalf of The Globe and Mail have not responded to requests to discuss the test.

But as far as the company knows (and police do not generally keep them updated), Dr. Frudakis said, the test has contributed to six arrests internationally. The most prominent example comes from Louisiana where detectives used it to catch a serial killer.

Eyewitness accounts of a white man driving a white pickup truck, as well as an FBI psychological profile, had suggested it was a Caucasian man who was raping and killing women in the Baton Rouge area in 2002.

But crime-scene DNA the Florida company tested indicated the offender was 85 per cent sub-Saharan African and 15 per cent Native American. In short, the test told police they should not be looking for a white man. Two months after the shift in focus, Baton Rouge police arrested Derek Todd Lee, a black man now on death row for the slaying of six women.

Asked whether RCMP hunting a possible serial killer in Edmonton might consider using the technology, spokesman Corporal Wayne Oakes would say only that investigators on the case are "aware of this technology, but it's not one they have had occasion to use."

Sergeant Don Kelly of the Baton Rouge police force said in an interview that one of the detectives involved in their serial killer case has made a presentation to police in Edmonton. But he could not say if the technology was discussed.

In some cases, the test has been helpful in identifying victims of a crime.

Police in Southern California, for example, had been targeting Asian gangs after discovering skeletal remains at Mammoth Lakes Park that bone-structure experts felt belonged to an Asian woman. But the Florida test found the woman was largely Native American, prompting park rangers to recall that a woman who fit that description had complained about her husband's abusive behaviour.

The test, which costs $1,000 (U.S.), scans 176 particular genetic mutations that each offer information about a person's continent of origin. The results then break DNA inheritance down into percentages of four geographic groups: sub-Saharan African, East Asian, European and Native American.

The company refers to the process as an estimate of "biogeographical ancestry" and from this, investigators can indirectly infer key physical traits -- in particular skin, eye and hair colour.

Of the 8,000 DNA samples they have tested by this method in the course of their research and work, 95 per cent of people turn out to be of significant mixed heritage, said Zach Gaskin, a technical co-ordinator of forensics at the company.

Still, Mr. Gaskin said, once a DNA sample suggests that at least 30 per cent of a person's heritage belongs to a particular racial group, a person starts "to exhibit features consistent with that population."

But in a paper published in American Psychologist, U.S. sociologist Troy Duster and ethicist Pilar Ossorio caution that the test has risks: "Some percentage of people who look white will possess genetic markers indicating that a significant majority of their recent ancestors were African. Some percentage of people who look black will possess genetic markers indicating the majority of their recent ancestors were European.

"Inferring race from genetic ancestry may mislead police rather than illuminating their search for a suspect."

For these reasons, company officials in Florida do not actually interpret test results by trying to describe shades of skin or hair colour. Instead, they provide photographs taken from their sample database of 2,500 people who match the genetic mix of suspects.

Stanford's Prof. Cho criticized this technique, however, arguing that even children from the same family can look very different from one another.

Toronto police Detective David Needham of the major sex crimes unit applauded the technology and said it is scheduled to be presented at a conference the force is holding in October.

"If the science is reliable and it can be accepted and established in the courts, it's going to be great," he said.

But he knows firsthand about the controversy it attracts.

A year ago, Det. Needham was hunting two men who had abducted and raped a woman who had seen only one of her attackers. To narrow his search for suspects, Det. Needham asked experts at Ontario's Centre for Forensic Sciences to try to give him a sense of racial background based on semen samples.

"They said, 'We can't do that, that's racial profiling,' " Det. Needham said. "If someone said they had seen a white man or a black man leaving the scene of the crime, we would use that information. So what's the difference?"

Bruce O'Neill, spokesman for the Ministry of Community and Safety and Correctional Services, which oversees the CFS, said the technology at hand has nothing to do with racial profiling.

Tim Caulfield, director of the Health Law and Policy Institute at the University of Alberta, noted that if the technology is indeed a sound tool for determining a suspect's physical appearance, it could turn out to be more reliable than eyewitness accounts.

"With a witness, there may be a whole set of social stereotypes that come out," he said. "If this technology is providing information that is factual, and people don't use it to make unwarranted presumptions, then it could be worthwhile. We need to be careful about how we let politically correct concerns colour our views."

Yet such concerns are bound to grow right along with the power of genetics.

The Florida firm, for example, is now developing 3-D technology to read gene types to infer physical traits such as hair texture, skull shapes or the distance between the eyes. Dr. Frudakis predicted that such technology might allow them within the decade to generate a crude sketch of a suspect from a DNA sample.

If all this sounds more like an episode of CSI: Crime Scene Investigation, the popular television program that plays up the power of forensics, it is just a brief trailer for the plot lines to come.

Profs. Duster and Ossorio note police will eventually be able to discern psychological characteristics from DNA samples and generate behavioural profiles of subjects.

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