Martinko was stabbed to death inside her Buick on Dec. 19, 1979. She had gone to Westdale Mall in Cedar Rapids to buy a coat after a choir banquet. Her body was found early the next morning, with stab wounds to her face and chest, KCRG reports.
Jerry Lynn Burns, 64, was charged with first-degree murder and is scheduled to appear Thursday in Linn County Court.
Cutting-edge DNA technology was used to solve the cold case. A DNA sample from the crime scene was sent to the Combined DNA Index System, or CODIS, on Oct. 2, 2006.
It went unmatched for nearly 10 years. Last year, Parabon Nano Labs used the sample to create 3-D models of the suspect's face. The lab helped narrow down the pool of suspects by uploading the DNA to a public genealogy database and identifying distant relatives.
Building on DNA: How imaging technology could help solve cold cases
"The police department later collected covert DNA from the suspect," Jerman said. "The collected DNA was a match."
"This is a breakthrough in crime solving," said CeCe Moore, Parabon's lead genetic genealogist. "With these techniques, we can allow law enforcement to focus in more quickly on the right people. Eyewitnesses aren't always correct, but this is a genetic witness. This is unbiased."
Investigators questioned Burns at his workplace in Manchester, where he denied killing Martinko, but he couldn't explain why his DNA was found at the crime scene.
Martinko's classmate, Elizabeth Laymon, has been waiting for this day.
"Her parents didn't get to see this day come. Her sister is still alive and well," Laymon said. "It's still great to finally hear those words that we've been wanting to say for so long: 'We caught him.'"