Three-person babies IVF technique ‘safe’
http://www.bbc.com/news/health-36481452
Three-person babies IVF technique safe
Fergus Walsh
Medical correspondent
8 June 2016
The use of an IVF technique involving DNA from three people to create a baby has moved a step closer with a study that shows it is safe. Scientists at Newcastle University are trying to help women who are at risk of passing on serious genetic disorders to have a healthy child. Last year the UK approved laws to permit the procedure, which involves using donor DNA from a second woman.
The study in Nature found the technique will lead to normal pregnancies.
The process, known as "early pronuclear transfer" involves removing the parents' key genetic material from an embryo within hours of fertilisation, leaving behind the woman's faulty mitochondria. The parental DNA, which contains all the key genes responsible for character and appearance, is then transferred into a donor woman's embryo, which has its nucleus removed but contains healthy mitochondria. Last year the UK became the first country to approve laws to permit the procedure.
A study involving more than 500 eggs from 64 donor women found that the new procedure did not adversely affect embryo development and significantly reduced the amount of faulty mitochondria being passed on.
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But the studies showed the technique was not always successful. The amount of faulty mitochondrial DNA transferred during the procedure was less than 2%. However, one in five of the stem cell lines created from the embryos showed an increase in carryover of defective DNA from the original embryo.
Prof Turnbull said: "Our studies on stem cells does express a cautionary note that it might not be 100% efficient in preventing transmission, but for many women who carry these mutations the risk is far less than conceiving naturally."
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