Edmonton police say they are using DNA phenotyping, for the first time in its history, in trying to solve a sexual assault.
DNA phenotyping predicts physical appearance and ancestry from unidentified DNA evidence, and police use that information to narrow suspects and generate leads in criminal investigations.
Det. Colleen Maynes says the method is a last resort after all other investigative avenues have been exhausted.
"This was a vicious assault," said Maynes, adding she doesn't want to see the perpetrator act again.
A woman lost consciousness after she was violently sexually assaulted by a man who followed her from a bus stop in the central Spruce Avenue neighbourhood in March of 2019.
She sustained serious injuries and was found wearing only a shirt when it was -27 C.
"This survivor deserves justice," said Maynes.
There were no witnesses, surveillance video, public tips or DNA matches in the case.
Detectives enlisted DNA technology company Parabon NanoLabs in Virginia to help in the investigation. The lab has provided DNA phenotyping to help with other files in Saskatchewan and Ontario.
Most DNA testing in Canada goes through the RCMP's lab. Maynes said this can take a long time, as the RCMP deals with cases across the country and doesn't have the resources or technologies that other labs do.
"We are lacking with that technology here in Canada," said Maynes.
Paula Armentrout with Parabon said that since 2018, its labs have helped solve 230 violent crimes in North America, although not all of them used DNA phenotyping.
DNA phenotyping is not exclusive to sexual assault cases. The analysis has also been used to find possible suspects in murder cases and to identify remains.
With a computer-generated snapshot in the Edmonton sex assault case, DNA phenotyping determined the suspect to be a Black man with dark brown to black hair and dark brown eyes who stands about five-foot-four.
Armentrout said the turnaround for this type of analysis is about 45 days after receiving a DNA sample.
Police said the suspect's description may impact a marginalized community. After consulting with community stakeholders and considering the severity of the assault and the threat to public safety, police released the details with a computer-generated image.
Any leads generated from the image will require further investigative steps, said Maynes.
"It is by no means an immediate path to accusing a suspect," she said. "What it does is potentially give us leads in a cold case, and we can follow up with DNA testing from there."
This report by The Canadian Press was first published Oct. 4, 2022.
This story was produced with the financial assistance of the Meta and Canadian Press News Fellowship.
Angela Amato, The Canadian Press