Quebec cold case murder suspect ID’d with help of DNA research tool, trial hears

SAGUENAY, Que. — A forensic biologist has told a trial that a DNA research tool helped police hone in on the suspect who is now charged with the sexual assault and murder of a junior college student nearly 24 years ago.

Valérie Clermont-Beaudoin testified today at the Saguenay, Que., jury trial of Marc-André Grenon, who is charged with the first-degree murder and aggravated sexual assault of Guylaine Potvin in April 2000.

Clermont-Beaudoin said the unidentified male DNA collected at the crime scene was run through a database called “projet patronyme,” which analyzes the Y chromosomes of DNA samples and suggests surnames that could be associated with them.

She explained that Y chromosomes are passed down from father to son, as are last names in most cases, which allows biologists to identify tentative last-name matches for unknown DNA.