Man Finds His Son Carrying His Dead Twin's DNA, Not His, In A Case Of Human Chimera

One 34-year-old man failed his own son's paternity test. The son was carrying not his father's DNA, but his uncle's---a twin that was long dead.

Now this is the first reportedly strange paternity test "fooled" by a human chimera. This is a person who has extra genes---those of a twin's, who got lost in early pregnancy. His genes live on, though, according to The Independent.

An American couple, who took the help of a fertility clinic to conceive and give birth to a child, found that the healthy baby did not have the same blood type as either of his parents'. The worried father took a paternity test and found, to his distress, that his DNA did not match that of his son's.

The distressed parents thought that there might have been a mix-up with the sperm used by the clinic, but the clinic assured them that it was not so, reports Fox News.

Stanford University geneticist Barry Starr gave some fresh advice. He told the father to take a DNA ancestry test, which showed that the child carried the genes of his uncle, which made his father a "human chimera."

Other signs of human chimerism in his father's body included various tones in his skin and DNA variations in his semen.

Still, human chimeras are not really so rare, for one in every eight childbirths are thought to start as multiple pregnancies. Hence, there is a probability that cells from miscarried siblings would be absorbed in the mother's womb by the other child.