3 Famous Cold Cases Solved with Genetic Genealogy

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Between 1980 and 2019, about 185,000 cases of manslaughter and homicide remained unsolved. However, according to some sources, the total number of cold cases in the US is well above 200,000!

Until a few years ago, the chances of solving any of these cases were close to none; however, with the rise in interest for direct-to-consumer DNA kits in the last decade, things are taking a positive turn. With the help of DNA consultants and genealogy databases, many cold cases have been reopened and solved in recent years.

Here are some of the most famous ones.

The Golden State Killer Case

The Golden State Killer Case is undoubtedly the most famous cold case solved by investigative genetic genealogy. It’s also pretty recent, given that it was finally solved after more than 30 years in 2018.


Most of the crimes committed by the Golden State Killer, i.e., Joseph James DeAngelo, were committed in the 1970s and 1980s. In 2001, the police could tell by using DNA evidence that several crimes committed in the same area, including rapes and murders, were committed by the same person.


In 2018, the case was reopened, and law enforcement agencies started looking for DNA matches in the online genealogy databases. Many partial matches were found, and a family tree was built. The researchers narrowed down the tree until the only name remaining was the killer’s, and the information was turned over to law enforcement agencies for confirmation and prosecution. Joseph James DeAngelo was 70 years old when he was convicted in a court of law and sentenced to 12 life terms.

The Cobb County Rapist

This is one of the most famous cold cases solved with DNA phenotyping—a concept still fairly new to many. The case involved three rapes that took place in 1999 in Georgia, and while there was DNA evidence, there were no matches.


This is where the services of Parabon Nanolabs came in handy. The company specializes in DNA phenotyping, which involves analyzing DNA and using genetic markers to predict what a certain suspect might look like. Utilizing this technology, the police were able to get a rough sketch of the rapist, including the hair color, skin color, and eye color. Combined with a DNA profile that was submitted to a GEDmatch, a public genealogy database, leads were developed, which led to a distant ancestor of the rapist. Eventually, they were able to narrow the search down to a likely suspect whose DNA sample was an exact match to the DNA evidence in the police’s possession.

Helene Pruszynski’s Murder

This is another cold case from 1980 that was solved years later with the help of genetic genealogy. Helene Pruszynski first went missing, and later she was found in a field, raped and stabbed. They were no leads, and the case was closed.


Forty years later, a girl named Jesse Still used 23andMe and gave the police their first lead in Helene Pruszynski’s murder case. As it turned out, the murderer was a distant relative of Jesse Still—she didn’t even know him until the investigation led to him.

Needless to say, the process of finding criminals through DNA evidence is much more extensive and exhaustive than it appears here. If you’d like to learn more about it, you can reach out to our DNA consultants at DavisDNA And Family Research. We offer a wide range of genealogy services, including investigative genealogy services.