Hear audio from Jerry Lynn Burns’ preliminary appearance in Linn County on Thursday morning, Dec. 20, 2018.
Joseph Cress, Iowa Metropolis Press-Citizen

Earlier than an arrest was made in certainly one of Iowa’s most haunting cold-case killings, investigators collected DNA from more than one hundred twenty five individuals as they eradicated suspects. 

Search warrants unsealed final week show the efforts of Cedar Rapids investigators to make an arrest within the 1979 deadly stabbing of 18-yr-previous Michelle Martinko, which included taking buccal swabs from dozens of people. 

The warrants additionally higher clarify how a Virginia-based mostly genetics lab and the DNA of a lady in Vancouver, Washington, helped detectives determine the Manchester man they are saying killed the high school scholar many years ago when he was 25: Jerry Lynn Burns. 

Jerry Lynn Burns (Photograph: Particular to the Register)

Martinko was found lifeless, stabbed repeatedly in the face and chest, Dec. 20, 1979, in her family’s 1972 Buick in the Westdale Mall parking zone. Now a sixty four-yr-previous enterprise owner, Burns was charged in December with first-degree murder. 

Within days of the killing, police received more than 200 phone calls and letters from people who wanted to help. Hundreds of people were interviewed within the first year as detectives compiled a list of more than 80 potential suspects. 

In 2016, police sought the services of a company that specializes in DNA phenotyping, the process of predicting physical appearance and ancestry from unidentified DNA.

Using genealogy website GEDmatch, that company, Parabon NanoLabs of Reston, Virginia, later hypothesized that a Washington woman was a second cousin once removed from Cedar Rapids suspect. 

Parabon created a family tree with four sets of the woman’s great-great-grandparents at the top and told police the suspect was likely a descendant of one of those elders. The company said if officers could collect buccal swabs from living descendants, they could identify which of the four branches the suspect probably belonged to. 

Matthew Denlinger, a Cedar Rapids police investigator, collected DNA from two branches of the family tree, which were eliminated, according to the warrants. Denlinger then got DNA from a woman from the third branch, which Parabon used to suggest the suspect was likely one of three Burns brothers. 

Officers then covertly collected items that likely contained DNA from the brothers, two of whom were ruled out as a match. 

In October, Denlinger saw Jerry Burns drink sodas out of a plastic glass with a clear straw and retrieved it after he left it behind, according…