Daniel Noe, a native of Peoria, Ill., disappeared in the fall of 1978 at age 22, the Chicago Tribune reported Friday.
Noe's remains were found by hikers on a steep mountainside in Utah in 2010. But they weren't identified until after his brother Michael heard a television broadcast a year ago that Cook County sheriff's deputies trying to identify eight men killed by Gacy were asking for DNA samples from family members of young men who disappeared in the 1970s.
Gacy was executed in 1994 after being convicted of killing 33 teenage boys and young men between 1972 and 1978.
Deputies took DNA from Noe's parents. The samples didn't match up with any of Gacy's victims. However, a national database later linked them with the Utah remains.
Daniel Noe was hitchhiking from Bellingham, Wash., to Chicago when he disappeared. When his parents hadn't heard from him for several months, they filed a missing-person report with the Illinois State Police.