Suspected serial killer caught after relative shares DNA with genealogy websites

Think twice before you send companies your spit. 

A suspected serial killer was caught when investigators compared his DNA to samples collected by ancestry websites.

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Services like 23andMe and Ancestry have become popular by using DNA from users who want to learn more about their family history. But few people think the DNA samples they send in might be used by law enforcement. 

On Tuesday, Joseph James DeAngelo Jr.