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The Pentagon has a memo (literally) for military service members: Be careful about using at-home DNA test kits as they may prove a security concern.

“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,” states the memo sent to military members and first reported by Yahoo News.

The Pentagon missive is unclear on exactly how such data may impact national security, though the implication is that it might unveil sensitive information that could compromise service members. One key issue seems to be that military members are required to report their medical problems.

For one thing, these tests might lead to the “unintentional discovery of [biological] markers that may affect readiness,” which could in turn “affect a service member’s career,” Pentagon spokesperson Commander Sean Robertson told the New York Times.

The Pentagon is the latest to express concerns about basic issues that critics of consumer DNA test kits have previously raised. Those include uncertainty about how accurate such testing kits are, the quality of medical advice that can be gleaned from such services without the help of a professional genetic counselor, and a lack of privacy regulation in a quickly growing field.

DNA testing services such as 23andMe and Ancestry have exploded in popularity these past few years. As of this summer, 23andMe alone had 10 million customers—and that’s not even considering the recent 2019 holiday season, one of the most lucrative times of year for such companies.

Many of these firms market their products as a way to provide consumers ownership of their own genomic data without having to deal with the hassle of a doctor’s office. And, in some ways, they’ve won regulatory blessings.

For instance, 23andMe has Food and Drug Administration (FDA) clearance to market its direct-to-consumer tests and accompanying health reports for a number of conditions, including Alzheimer’s and various inherited diseases.

But questions remain about these tests’ accuracy—and exactly how consumers can use the information without clinical followup and genetic counseling. A 2018 study in the journal Nature found that up to 40% of certain at-home DNA test results may provide misleading results and false positives.

Then there’s the issue of privacy. Companies like 23andMe have linked up with drug firms like GlaxoSmithKline to use genetic information for drug development—albeit on a voluntary basis, according to the firm.

“All of our customers should be assured we take the utmost efforts to protect their privacy, and that the results we provide are highly accurate,” a 23andMe spokesperson told Fortune when asked about the Pentagon memo. “All of our testing is done in the US, and we do not share information with third parties without separate, explicit consent from our customers.”

The specter of ostensibly de-identified data becoming re-identified may also pose a problem down the line—after all, if forensic genetics can be used to catch a serial killer, it could be used to identify members of the U.S. military.

Pentagon Latest to Warn About Concerns Around DNA Test Kits

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