The Pentagon has issued a directive advising military members to beware of the growing popularity of the home DNA and ancestry kits, as they pose a higher security risk for military members than for their civilian counterparts.

The home kits are growing in popularity and are at this time of year a popular Christmas gift so that people can trace their ancestry. So far, in a study conducted by the Massachusetts Institue of Technology (MIT), over 26 million people have voluntarily sent their DNA to be tested. That number is expected to skyrocket to over 100 million by 2021.

That’s what worries some Pentagon officials. Under Secretary of Defense for Intelligence Joseph Kernan and acting Under Secretary of Defense for Personnel and Readiness James Stewart, said in a memorandum dated December 20, that DNA testing companies were targeting military members with discounts and other undisclosed incentives.

“These genetic tests are largely unregulated and could expose personal and genetic information, and potentially create unintended security consequences and increased risk to the joint force and mission,” the memorandum read. “Tests that provide health information have varying levels of validity, and many are not reviewed by the Food and Drug Administration before they are offered.”

“Moreover, there is increased concern in the scientific community that outside parties are exploiting the use of genetic materials for questionable purposes, including mass surveillance and the ability to track individuals without their authorization or awareness,” it stated, but gave no explanation of how this was being done.

Several of the more popular companies, Andcestry.com and 23 and Me which have targeted the military community with discounts, have publicly commented that they do not share their data with third parties, employers or insurance companies without explicit consent forms from the individuals.

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But consumer advocates warn all users, not just military ones, that their data can be sold by these companies in a variety of ways. It has been reported that some other companies have sold their data to third parties as well as law enforcement organizations.

However, back in July, the Navy’s Chief of Naval Operations, Admiral John Richardson, cautioned military members about using these DNA kits as he said scientific advancements are making biological weapons easily tailorable. 

“Be careful who you send your DNA to,” Richardson said. “There’s a number of those companies where you can go and find out what your makeup is. That’s a lot of information.

“You learn a lot about yourself, and so does the company who’s doing it,” the Admiral added.

U.S. Army using biometric data in Afghanistan. DVIDS

“It’s not hard to imagine a world where people are blithely sharing information online without realizing their third cousin is a Navy SEAL or an operative of the CIA,” said Erin Murphy, a former intelligence professional and now a professor at New York University’s School of Law.

“It all boils down to the same basic idea,” Murphy said. “In a world in which a few stray cells can be used to identify a person, there is no such thing as covert action, and no such thing as anonymity.”

The U.S. Army already uses biometrics to track and record data of Afghans suspected of being Taliban bomb-makers. They are  recording eye scans, fingerprints and facial images. These can be used when conducting operations or checking on possible insurgent activity. The Army is using the same method in Iraq as well.

So far about 1.5 million Afghans and 2.2 million Iraqis have had biometric data placed in databases. And that number is growing.