RACHEL MARTIN, HOST:
Britain is the country where the first test tube baby was born. Now, the United Kingdom is considering another groundbreaking - and controversial - fertility procedure. The British government appears ready to legalize a process in which a baby is conceived with the genetic material from three people. The science goes like this. Inside every mother's egg cells are all of her genes. All her DNA is packed inside the nucleus. And when she has a child, her DNA gets passed down.
But, there's also another thing inside that egg cell that mother passes on too - her mitochondria. About one in every 6,000 babies ends up getting defective mitochondria DNA from their mother. And a lot of the time, the defects are small. But sometimes, they cause muscle weakness, blindness, even death. In a new procedure, the mother would swap her mitochondria, if it was faulty, for a healthy third person's mitochondria.
Jessica Griggs, a writer with the New Scientist magazine in London, explains.
JESSICA GRIGGS: The idea with these techniques is to allow women that want to have a genetically-related child to have a child without the risk of passing along these faulty DNA.
MARTIN: But there are certainly those out there who are concerned about this procedure. Critics say this is a dangerous precedent that could lead to a world where scientists are allowed to create quote, "designer babies." Jessica Griggs says that maybe overstating it.
GRIGGS: That donor's mitochondria only contribute less than 0.2 percent of their overall DNA, which is a tiny amount and far less than you would get if you had a blood transfusion or an organ transplant. And that the public debate that we had in this country showed that most people rejected the idea of the donor being seen as a parent for this reason. You know, they would remain anonymous, they wouldn't have any rights to the child, that kind of thing.
And also, it's valid to say that the mitochondrial DNA themselves, they're not supposed to do anything in terms of making us, us. So all of the important genetic information, for example, that determines our appearance, intelligence, sporting prowess, that's all coded in the DNA from the nucleus that you get from both parents.
MARTIN: The British government plans a vote on this procedure next year.
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