After what is being described as “an historic debate”, the British Parliament today voted to approve the use of an IVF technique that critics say will lead to the creation of “three parent” babies.

UK Parliament

Parliament voted 382 to 128 in favor of the technique known as mitochondrial donation, which will prevent certain genetic diseases being passed on from parents to children; diseases that can cause a wide range of conditions such as fatal heart problems, liver failure, brain disorders and blindness.

Mitochondrial donation involves replacing a small amount of faulty DNA from a mother’s egg with healthy DNA from a second woman. The technique involves taking two eggs, one from the mother and another from the donor. The nucleus of the donor egg is removed, leaving the rest of the egg contents, including the mitochondria. The nucleus from the mother’s egg is then placed in the donor egg. This means that the baby would have genes from the mother, the father and the female donor.

The vote makes the UK the first country in the world to endorse this process. It comes at the end of what supporters of the measure described in a letter to Parliament as “seven years of consultation and inquiry that have revealed broad scientific, ethical and public approval.”

Mitochondrial donation is a controversial process opposed by many religious and faith-based groups who say it creates “designer babies” because it involves implanting genetically modified embryos, and because it could result in genetic alterations that might be passed on to subsequent generations.

While many scientists support the technique some have raised concerns about it. Among those are Dr. Paul Knoepfler, a stem cell researcher at U.C. Davis, (CIRM is funding some of his work). In a recent blog on the process Paul wrote that while he is not opposed to the technique in theory, he thinks this move at this time is premature:

“There is no doubt that mitochondrial diseases are truly terrible and need to be addressed, but if the potential outcomes from the technology are still vague, there are safety concerns, and it raises profound ethical issues such as changing the human genome heritably as is the case here, then my view is that a careful approach is both practical and logical. We cannot at this time have a reasonable expectation that this technology would be safe and effective. That may change in coming years with new knowledge. I hope so.”

Supporters in the UK say the science is already good enough to proceed. Dame Sally Davies, Britain’s Chief Medical Officer, calls it the genetic equivalent of “changing a faulty battery in a car.”

Professor Lord Winston, a fertility expert at Imperial College, London, says:

“I think the case is self-evident and reasonable. This is about something that is unusual and will benefit a small number of patients. I know there are some people who think it is a slippery slope that the next thing will be choosing intelligence or blond hair, but I don’t think that. For 20 years, it’s been scientifically possible to have sex selection of embryos; we still don’t allow it in Britain apart from for heritable diseases.”

It’s important to point out that while the House of Commons passed the regulations they still have to be approved by the House of Lords before they become law. A vote is scheduled for the end of this month. Even then any future trial involving the technique will still require the approval of the Human Fertilisation and Embryology Authority (HFEA) before it can go ahead.

Even if the process is ultimately approved in the UK it will likely face an uphill battle to be approved here in the U.S. where the debate over the ethical, as well as the scientific and technical implications of the process, has already generated strong feelings on both sides of the divide.