A DNA expert is reportedly testifying for the prosecution in the trial of American suspect Amanda Knox, accused of killing her British roommate while studying abroad in Perugia, Italy.
Police forensic expert Patrizia Stefanoni analyzed DNA found at the apartment where British student Meredith Kercher was fatally stabbed in 2007.
Amanda Knox and her former boyfriend Raffaele Sollecito are on trial for murder. They deny wrongdoing in Kercher's death.
Prosecutors in the case say that Kercher's DNA was found on the blade of a knife that may have been the murder weapon, while Knox's DNA was found on the handle. The knife was found at the home of Knox's ex-boyfriend, Sollecito.
Prosecutors also say Sollecito's DNA was found on the clasp of Kercher's bra. But the defense in the case says the DNA evidence might have been inadvertently contaminated.
The Associated Press contributed to this report.