'Human chimera': Man fails paternity test because genes in his saliva are different to those in sperm: It is thought cells from a miscarried sibling were absorbed by the man while he was in the womb
A US man has failed a paternity test after doctors revealed his dead twin, whose DNA the man absorbed in the womb, is the genetic father of the child.According to my mother, when she was pregnant with me, they didn't do ultrasounds, but there were two distinct foetal heartbeats heard, and she was supposed to be carrying twins. About four months into the pregnancy, my mother started bleeding badly, and after that there was only one foetal heartbeat, and she had to be on bed rest for the rest of the pregnancy or possibly lose me, too. For reasons I won't go into, we never had confirmation that she had miscarried my twin, but it is common and it sounds very much like that is what happened. My friend says I 'ate my twin'. I've often wondered if there were any residual effects from that. Did I absorb cells from that twin? And if I did...and say, it was a boy, could that be why I've had odd hormonal issues most of my life? [High androgens, for one.]
The 34-year-old man is the first ever reported case of a paternity test being fooled by a human chimera, someone with extra genes absorbed from a twin lost in early pregnancy.
Approximately one in eight single childbirths are thought to start as multiple pregnancies and occasionally cells from the miscarried siblings are sometimes absorbed in the womb by a surviving twin.