From birth to hybrid creatures

"Mater semper certa est" is a Latin legal proverb, "the mother is always certain". A woman who gives birth to a child, is without a doubt his mother. The Lydia Fairchild thought as she has to show for it prompted the beginning of the 2000s, a maternity test for her two children to get in the U.S. state of Washington, social assistance. A pure matter of form.

But instead of money, Fairchild got a subpoena. The officers opened her, she was probably an imposter, because the genetic test show clearly that it could not be the mother of their two children. On the other hand, the Test proved, however, that her life partner was in fact the father of the children. Fairchild was desperate, she tried to prove her motherhood by other means. However, even the birth certificates and pictures of her pregnancy didn't help anything, the officers believed her. A suspicion began to grow: she Has taken may be the children or surrogacy is hiding?

A court ordered that the birth of her third child – Fairchild was pregnant again – a witness. After the birth of the mother as well as the newborn was taken back to the blood. The Test showed that Fairchild is not even your third child is genetically the mother.

The twin sister lived in your

How is that possible? Puzzled and perplexed, the investigators began to undertake further investigations and met with a similar case from the year 1998. Karen Keegan, a woman from Boston, needed a kidney transplant and is not found in the search for potential donors that she was genetically of two of her three children to the mother. The Doctors went to the thing on the ground, and took DNA samples from various tissues and cells. It came to the big Surprise: Keegan, genetically considered, two people in one. This means that she was the product of two fertilised eggs, which were merged in an early stage of development to an Embryo. Normally, Keegan had a twin sister. Now this just lived in it.

Scientifically speaking, is Keegan, a "Chimera". Lydia Fairchild also, as in the case of later genetic testing of various fabric turned out, so about from the neck of the womb. The Tests proved that the DNA in Fairchild's blood cells of the cervical cells difference, are actually different from that in the same way as fraternal twins. These Tests rehabilitated Fairchild, because the DNA from the cervical cells fit – she was actually the biological mother of their children, and thus social assistance be entitled.

This incredible and many other exciting stories to genetics, the science writer Carl rooms is told in his book, "She Has Her Mother's Laugh".

There is also in the real world, in biology, chimeras.

chimeras are known mainly from the mythology, as the mixed creatures of humans and animals – mermaids, sphinxes or centaurs. For a long time they belonged exclusively to the realm of myths and legends. But since a few years, the awareness of the longer the more There are in the real world, in biology, chimeras.

Clear, blatant cases of Karen Keegan and Lydia Fairchild are extremely rare – at the University hospital of Zurich, for example, even the renowned specialist in Reproductive medicine, Bruno Imthurn has never heard of a similar case. However, chimeras without DNA to discover Tests is also difficult, especially when two same-sex twins are fused to a Person. At best, different-colored spots on the skin are an indication, or eyes of different colors. Otherwise, if two different gender be twins to one Person, then at most a hermaphrodite. How often such drastic forms of Chimerism, however, is completely unclear.

it is becoming Increasingly clear that Chimerism is not an anomaly of nature, but rather a program. Hybrids are much more common than you might think, probably most of the people are even small chimeras, so-called micro-chimeras. Because virtually every one of us carries foreign cells in the mother, or earlier-born siblings, for example, and even years after your own birth.

cells of the placenta-a barrier to overcome

Responsible for the placenta. For a long time it was believed that the placenta form an insurmountable barrier between the mother and the child. It is not so: "The placenta is much more permeable than previously thought", - quotes the magazine "Psychology Today" the biologists Kirby Johnson of Tufts University in Boston. So swimming in the blood of every expectant mother so many fetal proteins and DNA molecules, that one uses these today for hassle-free prenatal testing, the so-called non-invasive prenatal tests (NIPT).

But also all the cells of the placenta can overcome the barrier in two directions: on the Maternal cells are not able to get into the fetus, it is however, much is known. Conversely, a child penetrate cells in the body of the mother. Most of these cells are attacked by the maternal immune system and eliminated, a few sneak in, but parts undiscovered in different parts of the body and implant themselves there and become a part of the maternal tissues, and organs.

fetal cells can be found in the whole body of mothers: in the heart, the liver, the spleen, the kidneys, the skin, of the pancreas, in the intestine and many other tissues. In 2015, the investigated Dutch researchers tissue samples from 26 women who had died during pregnancy or shortly after the birth of a son. In the case of some of the dead women, the researchers found a baby cells in all organs examined. Even up to the brain, the fetal cells migrated to – they overcame by the placenta - the blood-brain barrier: In five of five examined brains, the researchers child discovered cells. In another study, U.S. researchers found in two of three examined female brains cells with a Y chromosome had to come from a son.

If the mother's immune system tries to eliminate the child's cells, as a hypothesis, it might attack the author's own cells.

What does all this mean? The functional cells of the sons in the nervous network of the brain affect the mind of the mothers? Hardly. What it means for the understanding of identity, when we know that we have cells of several individuals in our body? We feel then as a multiple personality? Hardly, also applies here.

Medically, however, the foreign cells are quite relevant, and in the negative as in a positive sense. So, you might be on the one hand, responsible for ensuring that women disorders suffer up to four times more likely to have certain auto-immune than men. If the mother's immune system tries to eliminate the child's cells, as a hypothesis, it might attack the author's own cells. Evidence provide studies that demonstrate a connection between the amount of foreign cells in the body and the risk of an autoimmune ailments such as multiple sclerosis or scleroderma to develop.

on the Other hand, there are also numerous references to the healing effects of the foreign cells. Because the fetal cells have properties of stem cells, can repair, for example, injured tissue, or even to protect against cancer, as some studies suggest. So women who develop breast cancer have, in General, less foreign cells than women without breast cancer. How strong are the protective and how stressful the harmful effects of foreign cells is still largely unclear. The research pokes there in the fog.

it seems Clear: We must get used to the idea that each Person is a little bit more than just you.

(Sunday newspaper)

Created: 09.02.2019, 17:34 PM