Mitochondrial donation is an emerging assisted reproductive technology that is used to minimise the risk of passing serious mitochondrial disease from mother to child.
Mitochondrial disease is caused by mutations that prevent the mitochondria from producing the energy the body needs. The mutations can be inherited via nuclear DNA or the mitochondrial DNA.
When there are mutations in maternal mitochondrial DNA – these will be passed from mother to child via the egg cell, although the nature and severity of mitochondrial disease will be impacted by the number of affected mitochondrial cells that are contained in the egg cell.
Mitochondrial donation uses a donor egg cell. The nucleus is removed from the donor egg and the other cell structures, including the mitochondria, are left in place.
There are two methods of mitochondrial donation:
- Pro-nuclear transfer: the nucleus of a fertilised egg is removed. The nucleus of a donor egg is removed. The fertilised nucleus is implanted into the donor egg.
- Maternal spindle transfer: the nucleus from the mother’s egg is removed. The nucleus of the donor egg is removed. The mother’s nucleus is implanted into the donor egg. This new egg is fertilised.
A person born after mitochondrial donation will be genetically related to three people; the donor, the mother and the father.
Western Australian legislation (external site) currently prohibits the use of an embryo that contains the genetic material of more than two people, and this is one reason why mitochondrial donation is not currently legal in Western Australia.
In 2021, after a Senate Committee Review and Community Consultation, the Commonwealth Government introduced the Mitochondrial Donation Law Reform (Maeve’s Law) Bill (2021) that proposes a staged approach to amending the Commonwealth legislation that currently makes mitochondrial donation illegal. This bill was passed on 30 March 2022.
Assisted reproductive technology legislation is being reviewed in Western Australia and the WA Government has committed to engaging with national consultations regarding emerging technology, including mitochondrial donation.