CHIMERAS ARE REAL! – Carla Beene

In my book THE TWIN WITHIN, the main character, 13-year-old Cassie Cortez, learns that before she was born, she had a twin who disappeared before birth. Vanishing Twin Syndrome is a real thing. Her twin, Orion, lives inside her as a bit of DNA. While Cassie struggles with cerebral palsy, she also has an odd trait – one blue eye and a brown eye, which possibly comes from her twin. She learns she is a Chimera. Different colored eyes are a characteristic of that condition.

In one part of the story, Cassie wonders if there are other Chimeras in the world. She discovers the true story of Taylor Muhl, a well-known American singer-songwriter, model, dancer, and Chimerism awareness advocate.

Here is an excerpt from Taylor Muhl’s blog:

I AM MY OWN TWIN

I was born a human Chimera, which is a rare genetic condition called Chimerism.

I’m a fraternal twin who fused together in the womb with my sister. Due to the fusion, I carry my twin’s genetic makeup within my own body. I’ve been told I have two sets of genetic makeup, two sets of immune and blood cells, along with other unusual physical attributes.

With my particular case of Chimerism, my doctors believe my body reacts to my twin’s DNA and cells as foreign matter. Because of that, it compromises my immune system, making it lower than the average person’s, causing me many autoimmune health issues. Also, I have sensitivities to foods, medications, supplements, jewelry, insect bites, etc. This doesn’t mean all Chimeras will or do have health or autoimmune issues.

I feel the most interesting aspect of my condition is my particular physical trait. Not all chimeras will have an outward physical trait, and you can still be a chimera without one. Chimerism can be difficult to detect, whether or not it involves a physical trait. I was born with a trait that caused two different skin pigmentation colors that run straight down the center of my torso, front and back. My pigmentation is on one side, and my twin’s pigmentation is on the other side. I’ve been told that the second color pigmentation is from my twin sister’s genetic makeup. It’s always visible on my torso, but it can become more or less prominent when my body temperature changes.

Some other physical traits I have, which are only on the left side of my body, are a double tooth and everything being slightly larger on that side than on the right. Also, I have food, jewelry, and insect bite sensitivities that react differently on the left side of my body.

PHYSICAL TRAITS THAT HUMAN CHIMERAS CAN HAVE

Two Different Colors of Skin Pigmentation