Investigative genetic genealogy helped confirm the identity of a Phoenix, AZ John Doe after his death more than two decades ago.
A man was found alive and unconscious on the sidewalk of Third Avenue and West Madison Street. Phoenix Emergency Medical Services transported him to St. Joseph’s Hospital where he was pronounced deceased on August 17, 2004. He had no identification on him when he was found.
For 20 years, his identity remained unknown. The Phoenix Police Department employed standard means of identification, including fingerprints and entering DNA evidence into the Combined DNA Index System (CODIS) which did not yield any results.
The Maricopa County Office of the Medical Examiner (MCOME) contacted the Ramapo College Investigative Genetic Genealogy Center, located in Mahwah, NJ, in September of 2024. Upon accepting the case, MCOME sent a portion of the bloodstain to Genologue in Tucker, GA, where a DNA extraction and whole genome sequencing was performed. In October of 2024, Genologue sent files to Parabon Nanolabs in Virginia for bioinformatics.
In November of 2024, the genotype files were received by the IGG Center and subsequently uploaded to GEDmatch Pro and FamilyTreeDNA to try and identify John Doe. Undergraduate students in the IGG Workshop course at Ramapo College began working on the case, but were unable to progress to an identification prior to the semester’s end. Between the last day of the semester and the winter break, staff in the IGG Center continued the work of the students and found two people related to the man, both third cousins.
The team advanced John Thiellesen as a candidate to Senior Medicolegal Death Investigator Christen Eggers of the Maricopa County Officer of the Medical Examiner. The Arizona Attorney General’s Cold Case Unit, led by Supervising Special Agent Roger Geisler collaborated with MCOME to obtain a family reference sample from a sibling of Thiellesen.
In March 2025, MCOME positively confirmed Thiellesen’s identity.
“I have had the honor of working with Ramapo College for the past couple of years and our collaborative efforts have led to not only this identification but many others in progress. Ramapo College has become a beacon of hope for individuals and families across the nation,” said Eggers. “Their tireless efforts have provided answers to countless families and demonstrates an unyielding dedication to the welfare of all people, regardless of their circumstances.
“This case showcases the power of investigative genetic genealogy to close longstanding missing persons cases,” said Cairenn Binder, assistant director of the IGG Center. “Every John and Jane Doe is the answer to a family missing a loved one, and we will continue to do everything in our power to keep restoring their names and providing those answers.”
“I’m proud of the work our Cold Case Unit is doing to bring answers and closure to the family members of missing and murdered Arizonans. With increased technology, and the right kind of cooperative approach between law enforcement agencies, there is hope for the loved ones of countless victims,” said Arizona Attorney General Kris Mayes.
If you have any information related to the cases the Arizona Attorney General’s Cold Case Unit is investigating or any other missing or murdered Arizonans, please submit your tip to the Cold Case Unit here, or by visiting Silent Witness.
Nationwide, the IGG Center, which is the only center of its kind to offer case work, research, and hands-on learning, has helped solve 28 cases and has 39 active cases.
Republished courtesy of Ramapo IGG