The great advances of the last few years in assisted reproduction, just leave us time to assimilate them. the scientific journal british "New Scientist" has reported a case of really extraordinary, of the first baby in the world that carries the DNA of two mothers and a father
Abrahim Hassa, a baby born five months ago in Mexico, my parents are jordanian, was conceived thanks to a novel assisted reproduction technique that uses the DNA of three different people, the father, the mother and a "second mother" - donor.
How is it possible?
Shaban, the mother of the baby carried by genes of the so-called Leigh syndrome, a disorder mortal that affects the nervous system in development. I had had two babies previously, but both died due to this condition. A quarter of their mitochondrial DNA carried the mutation that causes the disease.
With the help of the fertility specialist John Zhang and his team, looked for a way to avoid the gene carriers of the disease. One of these is the technique known as transfer pronuclear, which is involved in the fertilization of the ovum of the mother, the egg donor and the sperm of the father. Before the fertilized eggs begin to divide embryos are removed each core, and then is discarded of the donor to replace it by that of the mother.
By that technique was not accepted by the parents, who for religious reasons were opposed to the destruction of two embryos.
Then, what was done was to insert the nucleus of one of the eggs of Shaban in the egg of the donor, which had already been removed from its own core. The egg resulting nuclear DNA of Shaban and the mitochondrial DNA of the donor is fertilized with the sperm of the father. There were five embryos, but only one is developed in the normal way. It was implanted in the mother, and of him was born Abrahim nine months later.
A technique controversial
It is one of the latest revolutions that have taken place in the world of in vitro fertilization, authorized a year ago by the United Kingdom. It is a technique that is done in order to prevent the development of mitochondrial diseases. All the mitochondria that are transmitted to a child come from the mother. If the mother has a mitochondrial disease, all their children will inherit it. That is why the scientists searched for a way to prevent this to happen by involving in the process the mitochondria of a third person, another woman donor's egg with mitochondria healthy.
It is, in fact, a transplant of mitochondria (the energy center of cells) between two eggs. Is inserted the nucleus of an ovule of a healthy woman in the of a mother with defective DNA to be fertilized in vitro by the sperm of the father. That is to say, there would be two mothers and a father, although only 0.1% or 0.2% it would correspond to the mitochondrial DNA of the woman who donated the healthy egg.
The controversy is centered on the manipulation of embryos, creating babies "by design" in which you replace a "part" defective for another good, where is the limit?, ask the detractors. However, there are also those who advocate the technique as it will allow parents with birth defects to bring to the world healthy children. Do you what do you think?