Both Alt and his girlfriend are believed to be victims of a homicide.
Richard Thomas Alt was 31 years old when he was last seen by his parents on Christmas Eve in 1984. (Bucks County District Attorney's Office)
Alt's skull was found by a fisherman in June 1986 near the Morrisville Boat Ramp. The remains went unidentified for decades until Bucks County Detectives sent the skull to Othram Inc., a private forensic DNA laboratory in Texas, in September 2022.
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Scientists at the lab matched the skull with someone who uploaded their DNA profile to a public genealogy database. That match ended up being Alt's daughter, who was just 11 years old when her father disappeared.
"I’m just glad that we could give them some peace of mind with this identification, and the eventual return of his remains to his family," Bucks County District Attorney Matt Weintraub said in a statement.
"I hope that this powerful combination of technology and genealogy becomes the template for solving cold and current cases now and in the future."
Richard Thomas Alt's skull was found on the banks of the Delaware River in 1986. (Bucks County District Attorney's Office)
Law enforcement has turned to investigating genetic genealogy to crack hundreds of cold cases in recent years, such as Golden State Killer Joseph James DeAngelo.
Detectives have also been using genetic genealogy during their investigations of current cases. The FBI reportedly used the novel investigative method to zero in on Bryan Kohberger as the suspect in the slaying of four University of Idaho students last year.