Mitochondria are the tiny compartments inside nearly every cell of the body that convert food into useable energy. But genetic defects in the mitochondria mean the body has insufficient energy to keep the heart beating or the brain functioning. Cells can have hundreds of mitochondria which are passed on solely from mother to child. About one in 10,000 newborns are affected by mitochondrial disease. Many of these children die young, as the mutations cause the brain, heart, muscles and other energy-demanding tissues to fail.
The technique, developed in Newcastle (UK) combines the healthy mitochondria of a donor woman with DNA of the two parents.
Doctors in Newcastle are ready to offer the experimental treatment, called mitochondrial replacement therapy (MRT), to women whose faulty DNA puts them at risk of passing on devastating genetic diseases to their children. MRT was developed to help women with mutations in the DNA of their mitochondria to have healthy babies. MRT aims to prevent mitochondrial diseases from being passed on by replacing the defective mitochondria in a mother’s egg with healthy mitochondria from a donor. The resulting baby would inherit the full set of 46 chromosomes from its mother and father – it is this DNA that defines their appearance and other characteristics – but have the healthy donor’s mitochondria. The donor has no legal rights over the child. UK's historic decision means that parents at very high risk of having a child with a life-threatening mitochondrial disease may soon have the chance of a healthy, genetically-related child. The first British baby made with the DNA of three people could be born in 2017 after the UK’s fertility regulator gave the green light for clinics to seek licences for the procedure.
