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HAVING A BABY TO SAVE ANOTHER BABY´S LIFE

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You have probably read about a few couples who have had a baby in order to use his blood to save a sibling's life. In this article I'll explain to you why and how it is done, what are the risks and how much it costs.

Imagine that you have a baby that, among other things, two or three years after birth starts to lose his hair and is too small for his age. You take him to the pediatrician, and he tells you that the baby suffers from a disease called Fankoni's anemia. The condition will develop into leukemia, which will inevitable kill the child when it is about six years old, causing in the process a lot of pain for him and for the whole family.

Until a few years ago the only way to save this child was through a bone marrow transplant from a perfectly matched donor, which could only be a brother or a sister or, with lots of luck, a stranger. Perfectly matched means that the recipient and the donor must have the same set of genes that code for proteins whose function has to do with transplant rejection.

Many couples had a second baby hoping for the perfect match, but chances of that happening, except with twins, are very slim; and, besides, remember that the new baby must also be disease-free. In some cases after the mother is pregnant they test the fetus, and if it has the disease the couple chooses to abort it.

It is obvious that parents will do anything possible to save the life of a son. If they already are living through the pain of watching their son die day after day, they probably do not want to go through the whole thing again.

Some parents, of course, decide not to abort and try again. There is a problem with this: the younger the sick baby is the higher the possibilities that the transplant will succeed, because it is healthier. Thus, if the first attempt fails, the parents have to try again immediately, because time is running out and the sick baby is getting sicker.

Now, however, there is a new method that increases the chances of getting the perfect donor. A form of in vitro fertilization (IVF) called pre-implantation genetic diagnosis (PGD), this technology allows researchers to pick an embryo that they know is not only a perfect match but is free of the disease. To do this they take an ovule, fertilize it in vitro, wait until it has divided a few times and then, using genetic engineering techniques, screen it for the genes that indicate the match and do not carry the mutation. Finally, they implant it in the uterus of the mother and soon a healthy baby will be born.