Senate debates

Tuesday, 8 February 2022

Bills

Mitochondrial Donation Law Reform (Maeve’s Law) Bill 2021; Second Reading

1:24 pm

Photo of Murray WattMurray Watt (Queensland, Australian Labor Party, Shadow Minister for Northern Australia) Share this | | Hansard source

I'd like to begin my contribution. Obviously, I'll only get a few minutes before we go into two-minute statements, and we'll resume after that. I rise to speak on the Mitochondrial Donation Law Reform (Maeve's Law) Bill 2021. While I represent the shadow minister for health in this chamber, I offer my support for this bill as an individual senator, not on behalf of the Labor party opposition. It has been decided by the Labor caucus that the debate on and vote for this bill will be a matter of conscience for our members. This bill has been referred to as 'Maeve's law' after Maeve Hood. Maeve, at the time this bill was introduced, was a five-year-old girl living in Minister Hunt's electorate. Maeve, at 18 months of age, was diagnosed with Leigh syndrome, a severe type of mitochondrial disease. Maeve, by all reports, is a bright, bubbly child but struggles daily with the challenging medical issues arising from her disease. Maeve is one of thousands of Australians who suffer from mitochondrial disease. In fact, it is estimated that one in 200 people, or more than 120,000 Australians, may carry genetic changes that put them at risk of developing mitochondrial disease or other related symptoms, such as deafness, diabetes or seizures, during their lifetime.

Despite its prevalence, it's only in the last few decades that we have really begun to understand mitochondrial disease and its impact. Mitochondrial disease, or 'mito' as it's commonly called, is a very serious genetic disorder that affects mitochondria in our body's cells. Mitochondria, often referred to as the powerhouse of the cell, process oxygen and convert the food we eat into energy. Mito happens when genetic mutation within the mitochondria causes it to not function as it should, starving cells of energy. Mitochondrial disease is caused by a defect in the mitochondrial DNA of an embryo, which is a type of DNA passed on only through the mother—that is, passed on through the egg cells rather than the sperm cells.

Mito is a destructive and debilitating disease and can lead to multiple organ failure and death. Mito is a disease that often proves fatal for very young children. Up to 30 children born in Australia each week are at risk of developing mild to moderately disabling mitochondrial disease, while at least one Australian child born each week will develop a severe or life-threatening form of mitochondrial disease. It has proven very difficult to diagnose due to the range in severity and ways it can present. There are currently very few effective treatments against mito and, as yet, no cure, which leads me to the purpose of this bill.

The Mitochondrial Donation Law Reform (Maeve's Law) Bill 2021 seeks to allow for the staged introduction of mitochondrial donation techniques in Australia under a strict regulatory framework. Mitochondrial donation is an in vitro fertilisation technique to prevent the transmission of maternally inheritable mitochondrial disease from mother to child. Maternally inheritable mitochondrial disease refers to forms of this disease caused by changes in the mitochondrial DNA, which a child inherits only from its mother. This form of mitochondrial disease is the cause of approximately half of mitochondrial disease cases. Mitochondrial donation can assist in reducing the risk of mothers passing it on to their children. Mitochondrial donation involves transferring nuclear genetic material from the affected mother's egg into a donor egg that has had its nuclear DNA removed and retains only its healthy mitochondrial DNA.

It is important here to note the distinction between mitochondrial DNA and nuclear DNA. Mitochondrial DNA, while incredibly important for the smooth functioning of cells, represents a tiny fraction of our genetic material. Almost all of our genetic material is nuclear DNA, contributed equally by the mother and father. These are the more than 20,000 genes that make up our character, appearance and other qualities that form us as individuals. Mitochondrial donation does not alter the DNA that makes us individuals. The procedure only targets the tiny fraction of DNA that helps convert food and oxygen into energy.

While this procedure can be performed in a number of ways, the two techniques under consideration within this bill are maternal spindle transfer and pronuclear transfer. 'Maternal spindle transfer' means the transfer of the nuclear DNA from the mother into the donor egg, which happens before the fertilisation of the egg. It happens before the donor's egg is fertilised by the father's sperm. The second technique, pronuclear transfer, involves both the donor's egg and the mother's egg being fertilised. The mother's nuclear DNA is removed from her fertilised egg and inserted into the donor's fertilised egg, which has its pronuclear DNA removed.

Debate interrupted.