What she thought to be nothing more than a birthmark turned out to be her twin – a medical condition known as chimerism.
For as long as she can remember, the American singer and model Taylor Muhl had had a unique birthmark that split her torso perfectly in the middle – or at least so she thought. Once she decided to investigate she found out that she was a chimera.
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"I Am My Own Twin" I have a genetic condition called, Chimersim. I'm a fraternal twin who fused together with my sibling in the womb. I carry my twins genetic makeup within my own body, which is the second color skin pigmentation on my torso. There's only 100 cases documented in the world. I'm on a mission to spread Human Chimera awareness and it’s link to autoimmune. _ This photo was shot outdoors in natural light, in cold weather by celebrity photographer @jimjordanphotography My twins genetic makeup can always be seen outwardly on my body, but at times it's more prominent then others. _ I felt it was important to show my entire physical demarcation because in the entertainment business there's an overwhelming amount of pressure to appear physically perfect or within a certain physical stereotype. I hope by showing my own imperfections I can inspire others who have different physical traits or who are different, to never let that stop them from pursuing their dreams, to love themselves unconditionally and to know they're beautiful just the way they are! #chimera #chimeraawareness #taylormuhl
A chimera is an organism, in this situation a person, that has two different sets of genetic codes. This means that Muhl has two
She has two sets of DNA, two immune systems and two bloodstreams, one belonging to her and the other to her unborn twin.
There are few people around the world with the condition. In fact, only around 100 people have ever been diagnosed with chimerism.
— The Life Pile (@thelifepile) March 1, 2018
Chimerism happens one fetus absorbs the cells of a miscarried sibling while in the womb, leaving the surviving sibling with two sets of genes.
The diagnosis explained why Muhl had “many health challenges” throughout her life, including autoimmune disease.
Since she has two blood types, her own cells identify her twin’s cells as foreign and are constantly trying to exterminate them.
However, chimerism can be very tricky from a legal point of view.
In 2002, a woman named Lydia Fairchild was denied public assistance in Washington state when a DNA test proved that she was not genetically related to her children.
Luckily, her lawyer had heard about a human chimera in New England and proved that she too was one, and that one of her sets of DNA could have been related to the children.