Bioethics Blogs

A Cautious Approach to Mitochondrial Replacement

Françoise Baylis comments on the US Institute of Medicine’s report on Mitochondrial Replacement.


Today the Institute of Medicine (IOM) released a report, “Mitochondrial Replacement Techniques: Ethical, Social and Policy Considerations.” With this report, written at the request of the Food and Drug Administration, the United States is poised to proceed with research involving mitochondrial replacement.

Mitochondrial replacement research involves the transfer of nuclear DNA from an unfertilized or a fertilized egg (zygote) with dysfunctional mitochondrial DNA into a fertilized or unfertilized egg that has healthy mitochondrial DNA, and has had its nuclear DNA removed. Children born of this technology will have three genetic parents, insofar as they will have genetic material from a male sperm provider and two female egg providers.

This report, authored by the Committee on the Ethical and Social Policy Considerations of Novel Techniques for Prevention of Maternal Transmission of Mitochondrial DNA Diseases, makes a number of important contributions to the ethics and policy debates.

National Academies of Sciences, Engineering, and Medicine. 2016. Mitochondrial replacement techniques: Ethical, social, and policy considerations. Washington, DC: The National Academies Press.

The Committee’s approach to mitochondrial replacement technology is notably more cautious than that adopted in the United Kingdom. The Committee recommends limiting research to the intrauterine transfer of genetically modified male embryos, so as to avoid heritable genetic modification. Mitochondria are maternally inherited; fathers do not pass on their mitochondria to their children. In the UK there is no such limit. The US approach aims to avoid potentially harmful, irreversible, intergenerational effects (assuming that harmful consequences would relate to the mitochondria).

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.