Deceptive Labeling of a Radical Embryo Construction Technique

The British Parliament appears poised to give the go-ahead to a set of techniques for generating infants which, if implemented, would constitute the first cases of large-scale human genetic engineering. These techniques are widely referred to - by their scientist-creators and other proponents, by journalists, by bioethicists, by members of regulatory panels, by legislators, and even by some critics of the procedures - as "mitochondrial transfer" or "mitochondrial replacement." These scientifically inaccurate descriptions have been instrumental in easing the way to public acceptance of these manipulations.

What exactly are these techniques? An isolated nucleus from the egg of one woman is inserted into an enucleated (nucleus-lacking) egg of another woman. Done before fertilization, it is called "maternal spindle transfer" (MST). Done after, it is called "pronuclear transfer" (PNT). In fact, no transfer of mitochondria (the organelles that extract energy from fuel molecules and make it available for the cell's functions) is involved in these "three-parent" procedures. So why are they referred to as mitochondrial "transfer" or "replacement"?

The techniques are being promoted as a way of circumventing mitochondrial mutations, which...