Investigative Genetic Genealogy: Solving Cold Cases with DNA

The Nancy Guthrie Case

• 🔍 Investigators are using genetic genealogy in the search for Nancy Guthrie, who disappeared 17 days ago.
• ⚠️ DNA from a glove found near her home in Tucson, Arizona, did not yield matches in traditional crime databases.
• 💡 The FBI may now turn to genetic genealogy, a relatively new tool for crime-solving, to help resolve the case.

How Genetic Genealogy Works

• 🧬 Unlike traditional DNA testing, genetic genealogy uses an SNP profile as a 'roadmap' to find potential relatives, rather than just confirming identity.
• 🗺️ This roadmap utilizes publicly available genealogy databases where individuals have uploaded their DNA.
• 🌳 By building out family trees, investigators can make connections between DNA matches and eventually identify unknown individuals.

Successes in Cold Cases

• 🏆 The use of DNA and genealogy to identify unknown individuals gained significant attention with the identification of the Golden State Killer in 2018.
• 🗓️ Investigative genetic genealogists now help resolve cold cases almost weekly across the country.
• 🤝 Clearwater police, with the help of investigative genealogists, identified Edmund Gleed, a John Doe found in 1993, by contacting his 90-year-old son.
• 🎯 Recently, St. Pete cold case detectives used this process to identify a murder victim known as John Doe for 46 years, Johnny Bradshaw.

Public Participation and Databases

• 🗣️ Law enforcement may need to convince individuals to voluntarily provide DNA samples, as cooperation isn't always easy.
• ✅ Individuals who have used services like Ancestry or 23andMe can opt-in to databases that assist in solving cold cases.
• 🌐 Recommended databases for those wishing to contribute include GEDmatch, Family Tree DNA, and DNA Justice.
• ⚠️ It is important to note that consumer DNA tests do not automatically make your DNA searchable by investigators; users must explicitly opt-in.