Sons I gave birth to are 'unrelated' to me

The Telegraph ^ | November 13, 2003 | Roger Highfield

[NYer]

One human chimera came to light when a 52-year-old woman demanded an explanation from doctors after tests showed that two of her three grown-up sons were biologically unrelated to her.

Although the woman, "Jane", conceived them naturally with her husband, tests to see if she could donate a kidney suggested that somehow she had given birth to somebody else's children.

A study in the New England Journal of Medicine by Dr Margot Kruskall, of the Beth Israel Deaconess Medical Centre in Boston, Massachusetts, showed that Jane is a chimera, a mixture of two individuals - non-identical twin sisters - whose cells intermingled in the womb and grew into a single body.

Dr Kruskall believes the most likely explanation is that Jane's mother conceived non-identical twin girls, who fused at an early stage of the pregnancy to form a single embryo, according to a report published today in New Scientist.

For some reason, cells from only one twin dominate in Jane's blood - used for tissue-typing. In her other tissues, however, including her ovaries, cells of both twins live amicably alongside each other, hence the apparently impossible genetics of her three sons.

One son came from an egg derived from the twin whose cells dominate Jane's blood, while his brothers came from eggs derived from the other twin's cells.

Around 30 similar instances of chimerism have been reported, and there are probably many more who will never discover their unusual origins. Most chimeras probably go through life unaware of their unusual constitution.

[cajungirl]

I don't think the New England J Med would go along with that little plan. Ye cynical one. I would say that God's hand is in this.

[MHGinTN]

As I understand it, these were twin sisters having the same father and the same mother, two seprate embryos from two separate fertilization events concurrently occurring. Since we are diploid organisms (formed through the fusion of 23 chromosomes from father and 23 chromosomes from mother), even though the mitochontria of the two embryos might be somewhat different, the histocompatibility molecules would have a common father component. But I confess, I' don't even start to understand how this woman is a functioning chimera capable of reproducing off-spring of her twin!

[cajungirl]

Actually you are correct but your explanation would totally creep me out, mine sort of is within the realm of understandable or comprehensible. I couldn't personalize or comprehend being two people. But I could comprehend having parts of a dead twin. At any rate, this is fascinating to me to. There is actually no her, no set of dan that could be called her. Wonder what her brain is.

[MHGinTN]

mitochontria = mitochondria ... sheesh, it's all so complex!

[snowstorm12]

I don't think so because the children are the father's, just not the mothers.

[wizardoz]

It's pretty bizarre. I guess these embryos would have had to fuse before being implanted, eh? We're talking about embryos only days old... right?

[nickcarraway]

ping

[Qwinn]

"a more logical explanation would be that Jane got a little "freaky" with someone other than her husband and is grasping at straws for an alternative explanation...."

That would be, um, rather interesting. A cheating spouse would certainly account for a failed paternity test, but I fail to see how it could account for a test showing that a child coming out of a given woman's womb was not hers....

Qwinn

[MHGinTN]

You got it! I don't think twinning occurs past day fourteen from conception. The 'hatching' from the zona pellucida occurs around day four to six, so I would guess the two embryos had to be in proximity when they 'hatched' AND somehow the encapsulation of both got welded togewther to form one placenta while the embryo bodies welded together within a blastocele. Bee zar

[vetvetdoug]

The blue eye, green eye is not a chimera. It is a normal variant. The only way to test for a chimera is the DNA of each tissue from origin. Anybody that makes a diagnosis based upon physical examination with respect to chimeras or cancer is a fool (e). Fool is spelled with an "e" when something is really dumb.

[MHGinTN]

If a rapist was a chimera, could the semen have one DNA in the nucleus of seminal cells and the cells from say the mouth epithelials have a different DNA?

[MHGinTN]

Is it possible for an organ within a chimera to have two different DNA marked cells functioning within the organ?

[aruanan]

In such case, it's no wonder their DNA doesn't match the crime scene!

Read the article more carefully and turn down the bold.

[TaxRelief]

I was thinking about the "voices" part of schizophrenia.

[Billthedrill]

Ah, thanks. I thought it might be something like that. I am told that "genetic mosaic" is a lay term for the phenomenon.

So there it is, cajungirl - I may not be a doctor nor do I play one on TV, but I can assure you categorically that your daughter is not a Great Dane.

[Age of Reason]

Read the article more carefully

Why--which part of my former post contradicts the article?

[stands2reason]

So DNA tests can produce false negatives.

How is it "false"?

[Polybius]

Question for the Christians (or Muslims or whatever)..... how many souls will go to heaven or hell? One or two or ...?

Or another question:

Are souls assigned to bodies or are bodies assigned to souls.

[stands2reason]

Reread the article, a little slower this time.

[jerseygirl]

Amazing. Far surpasses the rarity of the woman who gave birth to twins- one African Amrican, and one Caucasian.