Cedric Meury

Cedric Meury, a software engineer living from Switzerland, has long been curious about his health. So he ordered a DNA test in May from a bio-tech start-up with operations in the U.S. and Europe run by a former Amazon product manager. But when Dante Labs' kit arrived in the mail, a few things seemed off. The return instructions and manual were missing. And the tube where he would have deposited his spit sample was filled to the brim with bubbly liquid and sealed up in a biohazard bag. At that point, Meury realized that he had been sent a used kit. The tube contained another person's saliva.

Cedric Meury

Cedric Meury

Meury fired off a letter with his concerns to Dante Labs and received a response within a few days acknowledging the mistake. Dante Labs' CEO Andrea Riposati said he's now aware of five people receiving used kits, including Meury, after looking into the matter. Ten customers have received fresh kits and a refund. In an email to CNBC, which the company subsequently posted to its blog, Riposati said the start-up used a third party to ship the saliva collection kits and return them using a UPS or FedEx prepaid shipping label. "For five orders, this partner printed the wrong return shipping labels and received the five kits back in its facility. Then, the partner managed these used kits as new units and fulfilled five new orders with them," he said. Riposati said the used kits did not disclose any personally identifiable information, so it didn't violate customers' privacy. The company didn't name its third party provider, stating that it took "full responsibility" for the mistake. It also stressed that its overall error rate is 0.5 percent, which it admitted is still "too high."

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