Woman gives birth, DNA test proves she’s not the mum 

Meet 40-year-old Lydia Fairchild: a Washington state woman who in 2002, at age 26, found out that after giving birth to her third child that she was in fact NOT the mother.

So who was? In the biggest twist as Fairchild was in a desperate battle to retain custody of her three children, it was discovered that her twin was the real biological parent – but she was her own twin.

If you’re still confused, then here’s where science comes in to explain Lydia’s condition: known as genetic chimerism.

The rare condition, derived from the name of a strange hybrid creature, the Chimera of Greek mythology, had been documented just 30 times throughout the world.

According to studies, those rare individuals, dubbed “Chimeras”, had started out as twins; but in the early stage of pregnancy, one of the twins had merged with and been absorbed by the other twin.

The cells of the consumed twin, however, did not disappear and remained alive in one concentrated area of their sibling’s body. In essence, a human chimera is one person made up of two separate sets of genetic material; they are, in fact, their own twins.

Back to Lydia, who was in the process of applying for the state welfare programme, was arrested for benefits fraud and taking part in a surrogacy scam.

Hospital records of her prior births were disregarded, as prosecutors called for her previous two children to be taken into care.

What saved Fairchild, was when a lawyer for the prosecution heard of Karen Keegan, a human chimera in New England, and suggested the possibility to the Fairchild’s lawyer, Alan Tindell, who then found an article in the New England Journal of Medicine about Keegan.

Tindell then realised that Fairchild’s case might also be caused by chimerism. As in Keegan’s case, DNA samples were taken from members of the extended family.

Further testing of Fairchild’s DNA confirmed that she was carrying two different sets of DNA, the defining characteristic of a chimera.

As proof that Fairchild was her own twin began to mount, the judge finally believed Fairchild was the biological mother of her children and dismissed the case.

“I probably wouldn’t have my kids today if they didn’t discover her situation. They wouldn’t have known to even consider me as a chimera,” Fairchild said in an interview with ABC News.

If not for Keegan, Fairchild said she might have lost her family forever.