With government agencies in the US and UK, considering allowing the use "cloning" technologies to prevent the transmission of mitochondrial disease, nuclear transfer has become a hot topic in Reproductive Medicine. As discussed in our prior blog post, IVF is used to obtain eggs from both the intended mother and an egg donor, and the nucleus of the egg (which contain the mother's genetic material) is transferred into the donor egg (which contains healthy unaffected mitochondria). British authorities have now issued a draft guidance document recommending letting research proceed on mitochondria donation. What will the USFDA recommend and will this type of research to help couples with mitochondrial diseases move forward? Only time will tell.