The United Kingdom's Human Fertilisation and Embryology Authority (HFEA) isn't going out quietly. Although the U.K's new coalition government plans to disband the agency later this year, HFEA today announced a scientific review into a potential new fertility treatment that involves swapping DNA from one woman's fertilized egg into that of another. This in vitro fertilization (IVF) strategy, described in Nature last year by researchers from Newcastle University, is intended to prevent the many different diseases that can result from mutations in the DNA of mitochondria, the energy-generating organelles in most cells. But the experimental IVF strategy is currently not allowed under U.K. law—HFEA must grant permits for such efforts—and it has provoked questions, in part because it would produce a "three-parent" embryo, one mixing DNA of the mother, father, and a mitochondrial "donor."
The procedure, which has worked in monkeys, would be for women who could pass on defective mitochondria—only a woman's mitochondria survive in a fertilized egg—to a child.
Researchers would take a fertilized egg and remove the two pronuclei, the sperm and egg's DNA before they combine, while leaving behind any mitochondria. This would then be placed in another woman's fertilized egg, after its own pronuclei have been removed. The resulting egg would then be implanted into the first woman using traditional IVF techniques.
In their study last year, Newcastle researchers showed that they can transfer pronuclei between human eggs, but they have not yet implanted any resulting embryos. They hope to be ready to do that within the next year or so, hence the need for HFEA to review whether the United Kingdom should allow the technique's clinical use. HFEA will be accepting comments on the new technique until 15 March, and after a workshop later this month, it intends to deliver a report to the U.K.'s Department of Health in January. "We are not ready to do this in patients now but the science is progressing very rapidly and we need to get Parliament to discuss this again now," Alison Murdoch, head of the department of reproductive medicine at Newcastle University, noted in a statement.