Three-Parent IVF: What's The Hurry?

With last week’s parliamentary vote, the U.K. is quickly moving ahead with plans to be the first nation to allow germline engineering of children via a controversial method of in-vitro fertilization.

So-called three-parent IVF involves the generation of an embryo using the DNA of three donors: the mother, the father and a donor woman whose egg, or oocyte, will house the nuclear DNA of both parents in order to circumvent the inheritance of rare mitochondrial diseases.

In the normal course of reproduction, all children inherit the mitochondrial DNA of their mothers. Mitochondria are small organelles found in the cytoplasm of the cell outside the nucleus and they contain their own comparatively small component of DNA. Their primary –but by no means only–role is to provide the energy the cell needs. But inherited mutations in some can lead to terrible diseases.

These include conditions such as Kearns–Sayre syndrome, which can lead to progressive blindness and blocked heart. It usually manifests itself before the age of 15. Another is NARP (neurogenic weakness, ataxia and retinitis pigments), also an early onset condition...