About 30 years ago, mother in the UK asked for her child to be medically examined because his face was quite asymmetrical, genetic analysis failed to detect any paternal DNA in his blood. After some complex genetic analysis doctors came to the rather startling conclusion that he was a parthenogenetic chimaera, about half his cells only contained DNA from his mother. The child died a few years later, but his death wasn't related to his condition.

They concluded it is was most likely an unfertilised ovum divided parthenogenically (without fertilisation), it almost formed a teratoma (ovarian teratomas form partenogenetically) but one half was fertilized by a sperm. The result merged to form a viable foetus.

The nearest recognised example of a human virgin birth.

Here is the article.

Strain, L., Warner, J.P., Johnston, T., and Bonthron, D.T., 1995. A human parthenogenetic chimaera. Nature genetics, v. 11, no. 2, p. 164–169.