There were differences in the samples recovered from the letters mailed to New York and those mailed to Senators Tom Daschle and Patrick J. Leahy.
Investigators have said that Mr. Malvo's DNA has been recovered from more than one shooting scene, including samples recovered from a grape stem and a candy wrapper.
Once Ballard's DNA was tested and Detective Ford learned that it matched the samples recovered from the crime scene, he confronted Ballard.
Artists intend to rely on photographs of the mural and paint samples recovered from scraping graffiti at the site to replicate the design and match the color of the paint used by Haring.
Mr. Acosta has been linked to 15 of the 16 attacks through a match of DNA samples recovered at the scenes of the sexual attacks, the police said, and from a saliva sample he provided to detectives before he escaped.
Trace DNA samples recovered from footprints in the Arctic snow have been used to reveal the bloody killing of a seal by a polar bear, which was joined by seagulls in devouring the corpse.
For the first exploration well into a previously undrilled basin to find net oil pay and with a number of oil samples recovered to surface is an extremely positive result.
Mr. Beach was arrested Wednesday after his DNA matched samples recovered in two rape cases and after a victim in a third case identified him in a lineup, law enforcement officials said.
Mr. Santiago, who also uses the names Raul Luis Acosta and Lito Acosta, was linked to 15 of the attacks through a match of DNA samples recovered at 15 of the crime scenes and a saliva sample he provided to detectives before he escaped from the Bronx Special Victims Squad on May 6.
Forensic experts testified that scientific evidence involving blood, semen, hair and DNA analysis had failed to uncover any links to the defendants, and that only soil samples recovered from the defendants' clothing "could have originated" at the secluded path where the attack took place.
Faced with the heart-rending but essential task of identifying victims of the attacks on the World Trade Center, the New York City medical examiner's office has made preparations to perform DNA testing on as many as 20,000 tissue samples recovered from the rubble, officials said yesterday.
