A rare occurrence involving DNA has just been reported in the US. A baby conceived by in vitro fertilization was found not to have the blood type of either parent and even the father’s DNA did not match that of the baby.
This distressed the parents who thought a wrong sperm was used. However further tests revealed that the father was a result of twin pregnancy in which the second twin died in the womb following the absorption of his genes by the one who survived in a rare process called chimerism, the man (father of the baby) is therefore a Chimera.
However, paternity was established by other tissue tests.