Published online by Cambridge University Press: 17 May 2016
It has been suggested that diseases linked to mutations in mitochondrial DNA (mtDNA) might be circumvented by transferring the nucleus from the egg of a woman with a mitochondrial disease to a donor egg from which the nucleus has been removed and discarded. Egg cell nuclear transfer would be a straightforward technique for preventing serious diseases, relying on a procedure used in embryo or somatic cell cloning. It might present a relatively uncontentious setting for the refinement of cloning procedures. Its proposal creates the opportunity to identify categories of germ-line interventions; explore whether ethical issues vary according to the category of germ-line intervention; and craft more precise policy guidelines in which graduated levels of germ-line interventions are recognized.