Boshonto Family

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THE MOTHER MADE OF TWO WOMEN

A mother stunned the medical world after tests showed she is made up of TWO women.

And even more incredibly she is NOT the biological mother of two of the children she conceived and had naturally.

Docs found the woman, named only as Jane, was formed from non-identical twin embryos who fused together in her own mothers womb. Her blood and some of her organs are made up of her own cells while other parts of her body belong to her unborn sister.

The amazing condition, which baffled doctors for two years, first came to light when Jane was given the bombshell news that two of her three sons did not share her DNA. That meant they could not be hers even though docs confirmed her husband was their father.

Finally Jane was diagnosed as a chimera, a person made up of two distinct sets of DNA. There have been just 30 known cases, though this is the first described in detail.

Janes bizarre story, reported in the New Scientist journal, began when she needed a kidney transplant. Doctors in the US city of Boston did blood tests on her three sons to see if they might be donors. Instead they found two of the boys could not be her own. Dr Margot Kruskall of the Beth Israel Deaconess Medical Center in Boston told how the results stumped her team and sparked a huge inquiry.��The report can be found in the May 16, 2002 issue of The New England Journal of Medicine.

She said: No-one could figure it out. One suggested Jane had secretly undergone fertility treatment using donated eggs. Another speculated she and her husband had got her sister to conceive with his sperm.

The breakthrough came when tests on Janes brother revealed the sons were all related to her family in some way or other. They then tested DNA from different parts of Janes body, including the thyroid gland, mouth and hair and were astonished to find they came from two different people.

An examination of her ovaries led to the conclusion that she must be the result of embryonic twins who already had their own reproductive organs when they merged. Cells from both twins existed in her ovaries side-by-side, meaning she could produce eggs with two different DNA fingerprints.

Dr Kruskall said the discovery meant there could be many more mothers and fathers who have no idea they are not their kids biological parents. And she warned it could have implications in custody battles.

Scientists also fear the number of chimeras will rise because increasingly common IVF treatment boosts the chances of conceiving twins.

Few years ago doctors in Edinburgh discovered a test-tube chimera who looked like a boy but had female reproductive organs. Other chimeras have shown outward signs such as eyes of different colours.

In short:

Guys, imagine if you discovered one day that two of your three children were genetically not yours. Recriminations, marital troubles, perhaps a divorce, right? But there is a chance, newly discovered, that can prove that they are really yours.
Now add a twist. What if you were these children�s mother? Suddenly the question becomes not �Who?� but rather �Huh?�

Yet that�s what happened to �Jane�. At the age of 52 when her children were full-grown, she and her children underwent genetic testing for a possible kidney transplant. Completely unexpectedly, two of her three children tested as genetically not hers. A mix-up of babies was ruled out, and she and her husband had not undergone in vitro fertilization, so it was absolute that her children were hers.

Jane, it turns out, is a human Chimera.

Suppose, in the case of Jane had the genetic anomaly shown up in the father rather than the mother, it is not only possible, but probable, that the first obvious explanation would have been the only one looked at, and the marriage would have ended up in divorce court rather than the New England Journal of Medicine.

for the folks who want to know more

GENETIC MOSAICS

A genetic mosaic is a creature whose body is built of a mixture of cells of two or more different genotypes. In mammals they arise by several different mechanisms:
� The fusion of two different zygotes, or early embryos, into one. (The reverse of the process that produces identical twins!) The resulting animal is called a chimera (after the monster in Greek mythology with a lion's head, goat's body, and serpent's tail)
� The sharing of blood supplies by separate embryos. This occurs with the occasional fraternal cattle twins and also - less often - with human fraternal twins who have shared the same placenta. Blood stem cells of each twin seed the bone marrow of the other. Only their blood consists of a genetic mosaic cells.
� During early development, errors during mitosis can produce stem cells that go on to populate a tissue or organ with, for example, a chromosomal aberration (e.g., aneuploid).
Example: Occasionally a baby is born with blood cells that have three copies of chromosome 21 (the same set responsible for Down syndrome). This can produce a leukemia-like illness that, fortunately, often disappears as that cell population declines.
� All female mammals are mosaic for the genes on the X chromosome because of the random inactivation of one or the other X chromosome in all their somatic cells.

more...

The Chimera is primarily known as a creature of Greek legend � a fire-breathing monster with parts of a goat and a lion with a serpent for a tail. In biology the term has come to refer to any organism that contains more than one set of genes. There are chimera African violets, where the core of the plant is genetically distinct from the outer layers. Animal chimeras, or mosaics, as they can also be called, don�t usually divide so neatly.

The most common form of human chimera is called a blood chimera. This happens when fraternal twins share some portion of the same placenta. Blood and blood-forming tissue is exchanged, and takes up residence in the bone marrow. Each twin is genetically separate except for their blood, which has two distinct sets of genes, and even two distinct blood types. Up to 8% of fraternal twins are blood chimeras, and as the incidence of fraternal twins in the general populace increases with the popularity of in vitro fertilization, the number of blood chimeras should rise proportionately.

What happened to Jane is a much rarer. Rather than a simple exchange of blood, she and her fraternal twin merged in utero, leaving only one fetus. The cells in her body are a mosaic of genes from both of the original embryos. The cheek cells from which the genetic testing was done were from one of those embryos, but at least some of the cells in her ovaries came from the other. Interestingly this genetic oddity gives her a better-than-usual chance of having a successful kidney donation, as her immune system does not reject as foreign either of two distinct tissue types. She would, however, be a poor candidate as a kidney donor were she in that position, due to the likelihood of two tissue types being present in her kidneys.

Many human chimeras show no overt signs of their condition. Others have more obvious physical findings. Doctors at the University of Edinburgh in 1998 had a patient referred to them for an undescended left testicle. However, when they examined him they could not find a second testicle. Instead they found something quite unexpected, an ovary and a fallopian tube. Their patient was a chimera formed from the fusion of male and female embryos. While this is a dramatic finding, most chimeras show more subtle signs, such as mismatched eyes, or parti-colored hair.

This sort of mosaicism is exceedingly rare in the medical annals, though not completely unheard of. To date approximately thirty cases have been found world-wide. However, most chimeras are unaware of their condition until some anomaly brings it to light. Given that, it is entirely possible that there are many more chimeras in existence.

KISU BUJHLAM NA

ar kao mone hoy bujhe nai

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