When you spit in a test tube in in hopes of finding out about your ancestry or health or that perfect, genetically optimized bottle of wine, you’re giving companies access to some very intimate details about what makes you, you. Your genes don’t determine everything about who you are, but they do contain revealing information about your health, relationships, personality, and family history that, like a social security number, could be easily abused. Not only that—your genes reveal all of that information about other people you’re related to, too.
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Gizmodo slogged though every line of Ancestry.com, 23andMe, and Helix’s privacy, terms of service, and research policies with the help of experts in privacy, law and consumer protection. It wasn’t fun. We fell asleep at least once. And what we found wasn’t pretty.

“It’s basically like you have no privacy, they’re taking it all,” said Joel Winston, a consumer protection lawyer. “When it comes to DNA tests, don’t assume you have any rights.”
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here’s what you need to know before giving away your genetic information.

Testing companies can claim ownership of your DNA

It’s unclear who has access to your DNA, or for what

Your anonymous genetic information could get leaked

If you sue and lose, you’re screwed

If companies get rich off your DNA, you get nothing

Source: What DNA Testing Companies’ Terrifying Privacy Policies Actually Mean

A very good article examining the privacy clauses of some genetic testing companies followed up by an analysis of what this means for the consumer. Be scared.