Half hen/rooster

[Bunnylady]

I don't know why I went haring after Rh compatibility - I know that's the mother's antibodies causing the problems. There's a similar problem in horses; it's particularly common in Friesians. What I was aiming for is the autoimmune diseases, and the many types of allergies where the body is going into full attack mode about things that really aren't threats (things like peanut allergies, which seem to run in families).

 

[cassie]

I think that was California, not Canada. The woman was applying for government assistance/child support; if the kids weren't hers, that's fraud. She was about to be arrested and prosecuted, that's how Social Services was involved.

I could have sworn that case was in Canada. But I could be wrong. Wouldn't be the first time. I do think it is interesting that it was someone in the prosecutor's office that read about chimeras, and suggested that the woman in his case be tested. I think he did so because they had on file hospital and medical records of the births of the children and also the sworn testimony of the father saying those were indeed her kids. I think they had testimony from the doctor that had delivered the babies also.

By the way, as to the woman who was the subject of the research paper the prosecutor read, according to her DNA she could not possibly be the parent of her children, but her brother could.

 

[cassie]

I just looked up the case. The woman's name was Lydia Fairchild and she lived in Washington. She has been the subject of a couple documentaries.

 

[Bunnylady]

I just looked up the case. The woman's name was Lydia Fairchild and she lived in Washington. She has been the subject of a couple documentaries.

I knew it was somewhere on the west coast of the U.S. Geographically, socially and politically it all looks pretty similar from this little corner of the country!

But the two cases you mentioned bring up an interesting situation - when the two embryos that fused are the same gender and are otherwise similar in coloring, how could you tell that the organism was a chimera? Why would one even suspect it? (I have known a couple of people with eyes that are two different colors - might they be chimeras?) I've seen pictures of horses that were chimeras; they looked rather like brindled dogs (though there is a brindle gene in horses, so not every brindled horse is a chimera). In the case of Lydia Fairchild, I believe they really had to go digging to get a sample of the "other" DNA; her skin and bone marrow and other easily accessible tissue all seemed to have come from the one source. To me, the most curious thing about the gynandromorphs is the fact that the tissue seems to be almost entirely segregated into "his" and "hers" sides, and the fact that they are, indeed, sides (though the paper in MamaRoo's link mentioned head/tail "halves" too).

 

[cassie]

The answer is that unless there is something distinctive you can't tell if an individual is a chimera or not. In Lydia's case, tissue from her cervix matched the children's DNA. And so did the DNA of Lydia's parents. The other woman found out she was a chimera when she needed a kidney transplant. When her children were tested to see if they would be suitable donors, according to their DNA they were not her kids. Several tissue samples were taken from her without solving the mystery, but then she remembered she had had a biopsy taken from her thyroid. Her thyroid tisssue was available and it differed from the rest of her DNA that had been sampled.

 

[KristyHall]

I'm enjoying this conversation

 

[cassie]

I knew it was somewhere on the west coast of the U.S. Geographically, socially and politically it all looks pretty similar from this little corner of the country!

But the two cases you mentioned bring up an interesting situation - when the two embryos that fused are the same gender and are otherwise similar in coloring, how could you tell that the organism was a chimera? Why would one even suspect it? (I have known a couple of people with eyes that are two different colors - might they be chimeras?) I've seen pictures of horses that were chimeras; they looked rather like brindled dogs (though there is a brindle gene in horses, so not every brindled horse is a chimera). In the case of Lydia Fairchild, I believe they really had to go digging to get a sample of the "other" DNA; her skin and bone marrow and other easily accessible tissue all seemed to have come from the one source. To me, the most curious thing about the gynandromorphs is the fact that the tissue seems to be almost entirely segregated into "his" and "hers" sides, and the fact that they are, indeed, sides (though the paper in MamaRoo's link mentioned head/tail "halves" too).

Just a comment. I once saw a picture of a human baby that was a chimera. It was half black and half white. Literally. Right up the middle. One side of the body was white and the other side was black. It looked like two babies had been stitiched together lengthwise. I don't remember if the two sides were the same sex or not.