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Genetic Genealogists


In 1984, the British geneticist Alec Jeffreys discovered the technique of genetic fingerprinting in a laboratory at the University of Leicester. These “DNA fingerprint tests” are now used to establish paternity, solve cold criminal cases, and help people to learn more about their heritage.

FamilyTreeDNA and Oxford Ancestors, the first commercial DNA testing and analysis companies, were founded in 2000. In the ensuing decades, other DNA testing companies began offering services to customers in response to growing public interest in DNA testing and genealogical research. It’s estimated that 30 million people have participated in genealogical DNA testing from one of the four major testing companies (23andMe, AncestryDNA, FamilyTreeDNA, and MyHeritage DNA), according to the Nebula Genomics Blog (

In 2010, the development of GEDmatch, a publicly accessible DNA database, prompted growing public interest in DNA analysis, and many people began uploading the results of their DNA ancestry tests to the site. Law enforcement agencies began to use GEDmatch; data from the FBI’s Combined DNA Index System, CODIS, database (which contains DNA profiles of persons who have been convicted—and in some cases—only arrested for crimes); and other sources of DNA information to assist in criminal investigations and identify crime victims. Investigative genetic genealogy (IGG), as it is known, has been used to identify more than 150 suspects in current and cold cases. In April 2018, law enforcement officials used IGG to identify Joseph James DeAngelo as the Golden State Killer. DeAngelo committed at least 45 rapes and 13 murders in California in the 1970s and 1980s. He was sentenced to life in prison without possibility of parole. The use of public DNA databases by law enforcement is a controversial issue, and the majority of for-profit DNA companies have banned IGG research in their databases.

There is also controversy regarding consumer DNA testing. Some consumer DNA companies have sold customer data to third parties without consumer consent. Despite the fact that consumer DNA companies have established stricter privacy and consumer consent protocols in recent years, these policies can be changed, and the customer may be unaware of these changes. The U.S. military also has concerns about consumer DNA tests. In December 2019, the Pentagon warned members of the Armed Forces not to take consumer DNA tests, saying “Exposing sensitive genetic information to outside parties poses personal and operational risks to Service members.”

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