(CBS) -- The effort to identify victims of serial killer John Wayne Gacy has helped solve the mystery of what happened to Edward Beaudion, a 22-year-old Chicago man who went missing in 1978.
At a press conference on Wednesday morning, Cook County Sheriff Tom Dart told reporters that the Beaudion family gave a DNA sample to police in 2011 after the department put out a call to families who thought their missing relatives might be unidentified victims of Gacy, who sexually assaulted and murdered more than 30 young men in the mid-1970s.
Beaudion disappeared after borrowing his sister's car to go to a wedding in July 1978. Dart said that about three weeks later, the car was found in Missouri and a man named Jerry Jackson was arrested for its theft. According to Dart, Jackson confessed to killing and dumping Beaudion, but wasn't charged because Beaudion's body was never found. Jackson died in 2013, reports the Chicago Sun-Times.
In 2008, Beaudion's remains were found by a family walking in a forest preserve. But, according to Dart, the DNA taken from the remains didn't get submitted until 2013. When the test came back, it showed a match for those submitted two years earlier by Beaudion's family.
Beaudion's sister told reporters that his family was thankful to finally have some closure in the case, and that they plan to put a cross in the spot where his body was left.
"I can't understand why [he was killed]," said Beaudion's sister Ruth Rodriguez on Wednesday. "I'll never get any answers for that, but at least putting the cross out there we have somewhere we can go and pray and connect with my brother."
Rodriguez and Sheriff Dart both encouraged people across the country with missing relatives to submit DNA samples to local authorities who can then compare them to samples from unidentified bodies.