Abrahim Hassan, a baby born five months ago, is the first person with three DNA after it was conceived with a new technique of assisted fertilization known as the “three parents”, as revealed on yesterday New Scientist magazine.
In reality, the procedure is only approved in Great Britain, it combines the DNA of three people: the mother, the father and a donor egg cell that is transplanted into the maternal nucleus. This prevents the baby from inheriting genetic diseases severe due to a defect in the mitochondria, the energy source of the cells. These defects are associated with over 200 diseases, from neurological to cardiac.
With this technique, the baby will not inherit his mother Leigh syndrome, a disorder that disrupts the development of the nervous system.
The parents of Abrahim, of origin the jordanian, had already lost two pregnancies. This time they made a new attempt in New York. But as the procedure is banned in the united States, the treatment was in Mexico. “Here there are no rules”, said John Zhang, a leader of the medical team, explaining the decision to travel to another country.
From your site online, the Fertility Clinic New Hope of New York, where he works Zhang, anticipates that he will present this first birth successful with a technique to prevent a genetic disease mitochondrial during the Congress of the American Society of Reproductive Medicine. This will be within two weeks, in Salt Lake City, Utah.
As reported in yesterday’s New Scientist, which anticipated the presentation of the next month, Abrahim was born on the 6th of last April and the doctors claim that they do not have signs of the disease.
Alison Murdoch, who leads the Fertility Centre in Newcastle, Uk, and leads the research in this field, praised the progress, but was cautious: “If the baby was born as is suggested, then it would be a great news”, said to several international media. “Translate the donation of mitochondrial in a clinical procedure is not a race against time, but a goal to be reached with caution to help ensure the safety and the possibility to play it”, he added.
instead, critics speak of genetic manipulation. Others questioned whether the treatment in Mexico, a country where there is no provision for cloning or assisted reproduction, as reported yesterday in the journal The Country, met the same quality standards that should be followed in countries with these standards.
however, the scientists working in this field claim that the term “baby of three parents” is wrong because the baby is born with two DNA that transmit genetic information that determines individual characteristics, such as the blood group, or appearance. Are the DNA in the nucleus of egg cell and maternal DNA of the sperm of the father.
The mitochondrial DNA is the “battery” that provides energy to the cell in order to work. “The mitochondrion is a part of the cell’s cytoplasm that acts during fertilization and fetal development. We now know that there are diseases, such as obesity, which destroy the mitochondria and this affects the chances of pregnancy or increase the risk of abortion,” he explained to THE NATION Ramiro Quintana, scientific advisor of the network of reproductive medicine and molecular Procrearte, that is testing with success the technique in mice and human oocytes donated for research.
The specialist explained that the mitochondria, which possess 37 genes maternal inherited by the baby, can produce more than 200 severe diseases, such as blindness, heart problems, muscle disorders, and even death, when they are defective.
“The nucleus of the egg provides us the information of how we will be, but that kernel can pass it you need to a mitochondria healthy,” he said, Quintana-. And that just brings the mother. When only agregábamos cytoplasm with mitochondria in healthy egg from a woman with mitochondrial defects, we helped a little to couples. Now, with this new technique, we take advantage of the machinery of cellular energy healthy.”
Although the description of this technique for the donation of mitochondrial with nuclear transplantation of the donor egg can be done in few steps, from the technical point of view it is as a microsurgery to level a millimeter. All, in a microscope. Then, there is that make the core transplanted to work properly with the new cytoplasm (see infographic).
“Before that, the injected cytoplasm of an egg from a younger woman to strengthen the cytoplasm of a woman with mitochondrial defects. The boys were born with a double genetic information mitochondrial. And that was banned. But this case, which did not include the use of embryos, but only of a donor egg, is different, ” said Quintana-. It opens a field very interesting application of this technique of assisted fertilization. In the future, when more equipment to master the high complexity, which has the procedure, the donation of mitochondrial could lead to many more applications.”
In this case, as described in the summary of the presentation that will Zhang the next month, retired from the nucleus of an egg of the mother of Abrahim and transferred to the egg, because without a nucleus, from a donor. The new egg, with the nuclear DNA of the mother and the DNA mitrocondrial of the donor, are fertilized with the sperm of the father. The team of Zhang got five embryos with this procedure, but only one was developed and implanted in the mother, who had a normal delivery at term.
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