An American singer has revealed that a unique birthmark led to the discovery that she has a rare condition that makes her her own twin.

Taylor Muhl's birthmark divides her body into two areas of skin with different pigmentation and after investigating she discovered she is one of only about 100 people ever to have chimerism.

This means she has two sets of DNA. It happens when one unborn child absorbs the cells of another miscarried sibling in the womb.

So the surviving baby carries some genes from the other baby. Muhl noticed differences between both sides of her body.

“Everything on the left side of my body is slightly larger than the right side,” she wrote on her blog. “I have a double tooth in the left side of my mouth and many sensitivities and allergies to foods, medications, supplements, jewellery and insect bites.”

A specialist in rare conditions revealed to Muhl that she is a chimera with two different immune systems and two bloodstreams.

Speaking to People, the model and singer said her first reaction was "shock", followed by "sadness".

"I was like, ‘Oh my gosh! I could’ve gone through life with a twin, with a sibling that hopefully I could’ve been close to.’ There was some sadness.”

Before she was diagnosed, she battled autoimmune diseases as her body identifies her twin's cells as foreign. However, finally knowing the reason why she says has given her "freedom".

“I felt like for the first time I could really breathe. Prior to that, every doctor said my stomach must have just been a birthmark… Finally, this is making some sense.”

Online Editors