In Washington state, one unnamed couple was shocked to learn that they conceived a child using the sperm of the male’s unborn twin. This makes the man not the baby’s biological father, but rather the biological uncle.
The baby was conceived through in vitro fertilization. After it was discovered that the newborn infant did not have the same blood type as the parents, it was thought that the fertility clinic made the awful mistake of using the wrong sample of sperm. However, this was later proven not to be the case.
Eventually, the DNA of everyone involved was more closely examined, and it was discovered that the newborn baby and the suspected father only shared 25% of the same DNA. If he was the biological father, the baby would have had 50% of his DNA. Soon the doctors confirmed the news. The baby shared 50% of the same DNA as the man’s unborn twin.
This meant that the unborn twin was the real biological father of the newborn baby.
This whole process started thanks to the genetic phenomenon known as “chimerism”. In chimerism, one unborn fetus that dies early into a pregnancy is later absorbed by the other sibling. This is commonly known as “vanishing twin syndrome”.
A chimera comes from Greek mythology and was an animal hybrid.
Surprisingly, this is much more common than most people think, as a study from 1998 found that one out of every eight single baby births originally started as multiples at the time of conception.
As the man involved in this case developed in the womb, he essentially became a “blend” of himself and his unborn twin brother. By “absorbing” his brother, he was later able to produce his brother’s sperm further down the road. He became a chimera.
The man also produces his own sperm. In fact, the other child that was previously conceived by the couple has been confirmed to be his biological offspring. According to experts, the odds that the man would have used his unborn twin’s sperm to conceive a child were only 10%. Thus, it really is remarkable that this ended up happening. It was essentially the “perfect storm” of chimerism.
So in the end, the child produced from this pregnancy will share more traits with a man who never lived to see his own birth than the man who actually used sperm that came from his own body.
It will be particularly interesting to see how the newly conceived child grows up to identify the father, who is actually the uncle.
Other chimeras have been known to have multiple skin tones, two different eye colors and sometimes even two sets of sex organs.
Needless to say, it’s simply amazing as to what can come out of the medical world.