MONTREAL, Quebec—Forensic science has led to what may be one of the biggest discoveries in the art world in years. A painting of a young woman, which sold at auction in 1998 under the assumption that it was by a German artist and created in the early 19th century, has revealed a clue as to who the real painter may have been: A fingerprint, left on the upper left-hand corner of the work, matches another found on a piece by Leonardo da Vinci.

Montreal-based forensic art scientist Paul Biro discovered the print, and carbon dating and infra-red analysis back up the claim. Professor Martin Kemp of Oxford University, who is writing a book on the discovery, has identified the portrait’s subject as Bianca Sforza, daughter of Ludovico Sforza, Duke of Milan, who lived in the late 15th century. If the work is indeed by Leonardo, its worth will be named as closer to $158,282,892 — a far cry from the approximately $20,000 it last sold for in 2007.

Read more at the Times (London).