Genetic screening study begins national roll-out

The Mackenzie’s Mission study has commenced recruitment of thousands of couples to determine their likelihood of having a child with a severe genetic condition.

Rachael and Jonathan Mackenzie

Rachael and Jonathan Casella and their daughter, Mackenzie, who Mackenzie’s Mission is named after. Mackenzie died in 2017 from the severe genetic condition spinal muscular atrophy when she was seven months old.

UNSW Sydney Professor Edwin Kirk is a lead investigator of a $20 million reproductive genetic carrier screening study which has begun full scale recruitment in four states and territories ahead of national expansion next year.

The pilot phase of the Mackenzie’s Mission study is now complete, with couples being referred for full recruitment in Victoria, Western Australia, NSW and the ACT. The study will extend to couples in Tasmania, South Australia, Northern Territory and Queensland next year.

In a world first, 10,000 volunteer couples will be tested to see if they carry the faulty genes that give them an increased chance of having a child with a severe genetic condition. They are being screened for about 750 conditions.

Prof. Kirk, a clinical geneticist at UNSW Medicine and Sydney Children’s Hospital said: “We are at a pivotal and exciting stage in the study. After spending the past year setting up the systems and procedures for broad-scale recruitment and piloting those, we are now confident about moving to the next phase.”

“We are looking forward with excitement to the next eighteen months; by the end of next year we will have learned a great deal about how best to deliver carrier screening for Australian couples.”

Couples can only be referred to Mackenzie’s Mission through health professionals at selected sites across Australia to ensure the data accurately reflects the demographic. Members of the 100-strong study team have been recruiting GPs and health professionals to participate.

The research project is administered by national research network Australian Genomics. The three lead investigators span three states: UNSW’s Professor Edwin Kirk (NSW and ACT), Professor Martin Delatycki from the Murdoch Children’s Research Institute (Victoria) and Professor Nigel Laing from the University of Western Australia (Western Australia).

The purpose of Mackenzie’s Mission is to determine how best to deliver reproductive genetic carrier screening at scale in Australia so that it is available for free to every couple who chooses to have it. Health Minister Greg Hunt has said he would like to see this in place within 10 years.

Professor Kirk said the three-year study would involve ongoing process refinement with each of the components evaluated. Once enrolment and testing are refined, the turnaround time for results is expected to be four weeks.

“This is a large, complex and ground-breaking study which requires considerable infrastructure and coordination – particularly with the testing laboratories – so it is important to ensure that all aspects are working smoothly,” he said.

More than 60 couples were tested across the three states during the pilot phase, which began last November. When fully operational the study will test couples either before they conceive or who are in early pregnancy. The recruitment of pregnant couples is on hold until the additional strain on laboratories due to COVID-19 is over.

The project was named after Rachael and Jonathan Casella’s baby, Mackenzie, who died at seven months from the severe neuromuscular condition, spinal muscular atrophy.

Mackenzie’s Mission is funded by the Australian Government’s Medical Research Future Fund (MRFF) as part of the Genomics Health Futures Mission (GHFM) grant. The grant is administered by the Murdoch Children’s Research Institute, through Australian Genomics.