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Tuesday 18 August 2015

Conceive babies in vitro with three DNA



After a long debate in society, British MPs Tuesday finally allowed the babies design from three different DNA to prevent the transmission of serious diseases. While it would be a very widespread therapeutic treatment, the UK installment in controversy and could become the first country to allow this in vitro fertilization process.
This decision was approved by 382 MPs against 128 must still be approved by the House of Lords on February 23, but it would be only a formality as informed observers. Therefore, the first babies born to two women and a man of DNA may arise from autumn 2016.
On average, 125 babies are born each year in Britain with mitochondrial dysfunction, transmitted by the mother. The mitochondria are small organelles present in cells that convert glucose into energy molecule. Defective, they cause an energy deficit in the body and are responsible for serious degenerative diseases such as diabetes or myopathy.
Technique developed at Newcastle
This technique makes it possible to block transmission of the disease from mother to child. It involves removing an egg from the mother the defective mitochondria to replace it with healthy mitochondria from another woman who remains anonymous.
After being fertilized by the sperm of the father in the laboratory, the egg is then implanted in the uterus of the mother. The future child will be a carrier of all genetic characteristics of his father and mother because mitochondrial DNA is less than 1% of the total amount of DNA contained in a human cell.
But the change will be permanent and will transmit generation to generation, an element at the heart of tensions aroused by the act.
For advocates of the art, it is a major advance. "We finally reached a milestone by giving women a valuable choice, that of becoming a mother without fear mitochondrial disease for their child," has thus welcomed Robert Meadowcroft, head of the campaign against muscular dystrophy.
This "gives families the first glimmer of hope of having a baby that can live free from pain and suffering," pleaded a group of international associations in an open letter to MPs. Lord Robert Winston, one of the pioneers of IVF has ensured that the procedure was comparable to a simple blood test.
Pandora's box
To his opponents, on the contrary, the provision goes too far in genetic modification and opens a Pandora's box for the selection of babies. "Once the border crossed ethical, once officially recorded that it is possible to manipulate the human genome, it becomes difficult not to take the next steps to achieve a world of custom made babies, a scenario that all world is to avoid ", warns David King of Human Genetics Alert association.
Professor René Frydman, scientific father of the first French test tube baby, also very reserved, saying it inadequately tested process. "With this germ line therapy, we modify the genome, is introduced 1% of a genome that comes from elsewhere and it is unclear what impact this may have," he told AFP, fearing Moreover it is exploited in the future to facilitate late pregnancies. One could indeed, he said, injecting mitochondria from a young woman and healthy to "rejuvenate the embryo" of a more mature woman and thus give it more chance to develop.
Several experts also warned against the greatest risks for children conceived in this way to develop cancer. The Catholic and Anglican churches of England have also expressed reservations. According to a survey by the institute ComRes, public opinion there was also reluctant. 41% of respondents said they were against a change in the law on embryology and human fertilization, which dates from 2008, against 20% who were for.
After modification of the law, all women of childbearing age affected by this genetic problem, and whose number has been estimated at 2,500, will not be eligible, however, the process automatically. They will go through the judgment of the British organization responsible for bioethics, the Human Fertilisation and embryology authority.

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