Abstract
Body development and activity depend on the level of internal energy generation. Therefore, unaffected, optimally active mitochondria are indispensable in a healthy and vital body. A mutation in the DNA of the semi-autonomous mitochondria (mtDNA) may cause an inheritable insufficiency that is due to decreased energy generation needed for adequate development. Sperm mitochondria will not enter the egg cell during fusion of male and female gametocytes. Since women with mutated mtDNA will increasingly know and realize the effect of such mutation in their own body, they will more often ask for treatment to stop the effect of such inconvenient mutation in their progeny. Thus far, solutions for this problem were thought to be: (i) nucleus transplantation just after fertilization into a nucleus-free egg cell of a second healthy woman and later (ii) transplantation of healthy mitochondria from a second woman into the egg cell before fertilization. Although both transplantations create babies with three, instead of two-parents that have contributed to the genetic content, in case of the newer mitochondria transplantation technique the part of the second woman is somewhat more reduced, but still clearly present. Thus, assisted-reproduction techniques that mix egg cell mitochondria from two women may create not only 'three-parents' babies, but also fears for 'three-parents' babies, since this handling may create non-scientific problems, especially regarding emotional, ethical, religious and juridical aspects of life. Transplantation of healthy sperm mitochondria of the partner into the egg cell with insufficient mitochondria is thought to be the best solution for this problem, since it may create a 'two-parents' instead of a 'three-parents' baby. This only implies that at the moment of (successful) transplantation the biological dogma is broken that mitochondria are maternally inherited: the mitochondria of the maternal line of the woman will have been substituted by the mitochondria of the maternal line of the man.
