1. MAPPING A FAMILY TREE TO CATCH THE GOLDEN STATE KILLER
DNA GENEALOGIST
MAPPING A FAMILY TREE TO CATCH THE GOLDEN STATE KILLER

2. FIRST, A BIT ABOUT DNA

3. How did the police find the Golden State Killer?
Genetic Genealogist
GEDmatch.com
23&ME and Commercial Genetic Testing Services

4. Genetic Genealogist
A genetic genealogist is a person who uses the outcome of DNA testing in combination with traditional genealogical research (family tree) and historical records, and other documentary evidence to infer the relationship between individuals.

5. Ancestry.com
“Your AncestryDNA results include information about your geographic origins across 500 regions and identifies potential relatives through DNA matching to others who have taken the AncestryDNA test. Your results are a great starting point for more family history research, and it can also be a way to dig even deeper into the research you've already done.”

6. https://dnatestingchoice.com/en-us/ancestry/provider/gedmatch/3845
GEDmatch.com
GEDmatch is a free genealogy website that allows you to upload the digitized genetic data you receive when you take a test with AncestryDNA, 23andMe, or Family Tree DNA. It was primarily designed to provide another layer of genealogical analysis, to help those who are looking for living relatives aka 'matches'. Jan 24, 2017

7. Read: Sooner or Later Your Cousin’s DNA Is Going to Solve a Murder
By Heather Murphy
April 25, 2019
New York Times

8. How did the Genetic Genealogist find the Golden State Killer using the online database GEDmatch?
The Golden State Killer’s second cousin, Brandy Jennings uploaded her Ancestry.com genetic file to GEDMatch to match her DNA with possible relatives she did not know.
Police collected DNA taken at the crime scene of a murder scene, presumably committed by the Golden State Killer and uploaded the DNA profile to GEDmatch.
Brandy Jennings DNA matched as a distant relative to the suspected killer’s through the GEDmatch database.

9. Police then used Genetic Genealogy and traditional police work to capture the Golden State Killer.
Brandy Jennings gave the police a break in finding the Golden State Killer. By building out her family tree, and by discovering the names of her siblings, and cousins, and 2nd cousins, where they have lived and during what years that they lived at those locations, police were able to verify DNA information through the traditional police work of interviewing suspects, and gathering and substantiating information like places of residence and employment. Police were able to narrow the pool of likely suspects to one man. A man that was the right age at the time of the murders, who lived in the area of the murders, and who’s DNA was found at the crime scene, Joseph James DeAngelo.

10. Read and Watch how DNA Genetic Genealogy identify suspects.
News Articles:
TCR Staff. “GEDmatch Puts DNA Database Off-Limits to Police: Will Cold Cases Get Colder?” The Crime Report. May 22,
Wang, Amy B. “Police revived a 1973 murder case by live-tweeting a girl’s last day. Now, a DNA match has led to an arrest.” The Washington Post. February 20, 2019 at 4:51PM. May 22, an-arrest/ar-BBTRUTZ
Murphy, Heather. “Sooner of Later Your Cousin’s DNA Is Going to Solve a Murder.” The New York Times. April 25, May 22,
Horton, Alex. “A suspected killer eluded capture for 25 years. Then investigator’s got his aunt’s DNA.” The Washington Post. February 17, May 22, aunts-dna/?utm_term=.372e58967fc8
Swenson, Kyle. “She swiped her co-worker’s Coke can. Police say it cracked a 28-year-old murder case.” The Washington Post. December 18, May 22, old-murder-case/?utm_term=.b0d486242ccb
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