Mitochondrial Donation in a Reproductive Care Pathway for mtDNA Disease.

Pathogenic variants in mitochondrial DNA (mtDNA) are a common cause of severe, often fatal, inherited metabolic disease. A reproductive care pathway was implemented to provide women carrying pathogenic mtDNA variants with reproductive options. A total of 22 women with pathogenic mtDNA variants have commenced or completed pronuclear transfer (and thus receipt of a mitochondrial donation), and there have been 8 live births. All 8 children were healthy at birth, with no or low levels of mtDNA heteroplasmy in blood. Hyperlipidemia and cardiac arrhythmia developed in a child whose mother had hyperlipidemia during pregnancy; both of the child's conditions responded to treatment. Infant myoclonic epilepsy developed in another child, with spontaneous remission. At the time of this report, all the children have made normal developmental progress. (Funded by the U.K. National Health Service and others.).