Human Genetic Chimeras
Man, it’s a tough blogging day when I start talking about recursive splicing of mRNA and the dissipation of energy from UV radiation along the DNA backbone.
Here’s a story from the entertainment section of the Philadelphia Inquirer about a mother who needed a donor kidney. The most likely matches were her three sons who, by the laws of Mendelian genetics, should share 50 percent of her genes. When they were all tested, though, none of her sons were a match. A hospital mix-up was ruled out because the boys’ DNA matched their father’s. Subsequent tests discovered that mom was a chimera.
Chimeras get their start when two or more eggs are released and fertilized by different sperm. That usually results in fraternal twins. Unlike identical twins, fraternal twins are no more genetically alike than ordinary siblings.
In a few cases, though, fraternal twins merge while in utero, becoming one single individual with a mosaic of different types of cells carrying distinct genetic codes.
The mother’s blood cells carried DNA from one twin, her ovaries and eggs carried DNA from another.
You can read the full story and more about human chimeras, which was originally published in New Scientist, November 15, 2003. It’s a cliffhanger – we don’t know if the mother ever got the kidney transplant she needed.
>In a few cases, though, fraternal twins merge while in utero, becoming one single individual with a mosaic of different types of cells carrying distinct genetic codes.
Does that make them conjoined mosaic fraternal twins?
I have subjective expeience with this.
the reason I found this article is because I think I am a chimera, or have chimera, or however u would put it into words.
I watched a program on the discovery health channel called ” I am my own twin”. To answer your question the Mother did recieve her kidney transplat. Her husband was a sutible match. I believe this to be more than possible. No one can say what happens in utero, and science is no where near being able to tell us everything that goes on those first weeks of pregnancy. My only question is when a child is born both male and female wouldn’t that be considered a Chimara? Since the baby would have both male and female dna? Making these cases not really as rare as they seem?
Dear Miranda,
In cases where they have both male and female genitalia, as well as both male and female DNA, then chimerism is a possible cause. (Some hermaphrodites – people with both female and male gentalia – have DNA that is only female, or only male, even though they have both sexes genitalia.)
But even so, cases of true hermaphrodites (having reproductive organs of both sexes as well as genitalia) with mixed female and male chromosomes is extremely rare, even if it is possible they are chimeras.
A chimera would make a good slave if a chimera is smart enough to understand
instructions but not smart enough to demand human equality for himself.
Just think…He will mow your lawn, clean your house, help you at work,
and as long as you love him, feed him and care for him, he’s happy.
I had a black cat named Velvet who was a chimera. She was a female cat with male testicles attached to her. However her testicles were not functioning. She was spayed like a female cat and the tomcats who liked her would try to find her at the window.
I had an elderly lady client named Frances I assisted with bathing. I brought her a washcloth and a basin of water. She was unable to use the bathtub and the shower. She sat ontop of a towel on the sofa. When I handed her the washcloth she bathed her private area and she had two testicles. She identified as a women. She got married and had two sons. I never said anything to her about it though.
I have seen two women who had male hormones because male hair was on their feet and toes. I have heard of women having male hair on their breasts.
Have you met animals or anybody like this before?
Chimeras do not always have both male and female sex organs. They can can be either male or female but have two different DNA.