Birmingham Womennewser

(NEWSER) – Sorry sir, you're not the father of your newborn child—your unborn brother is. So a 34-year-old man was told in the only known case of a paternity test being tricked by a so-called "human chimera," the Independent reports.

It began when a US couple learned that their son, born healthy in 2014 with the aid of a fertility clinic, had a different blood type than his parents. Concerned, the husband took an at-home paternity test and learned that his DNA didn't match the son's. "You can imagine the parents were pretty upset," Stanford University geneticist Barry Starr tells BuzzFeed. "They thought the clinic had used the wrong sperm." The clinic assured them there was no mixup, so the couple got a lawyer and approached Starr for help. On Starr's advice, the father and son took DNA ancestry tests and learned that genetically the dad was his son's uncle.

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