A clinical trial for pre-conception screening has been officially launched in Australia. The aim is to test the viability of a pre-conception screening programme for subsequent integration into the Australian health system. Researchers will assess its viability, psychological impact and ethics as well as potential obstacles to screening. Thousands of couples will be enrolled in the trial over a three-year period starting in 2019. The test will assess the risk of transmitting 500 genetic diseases.
Diseases related to the X chromosome and inherited as a recessive trait, such as spinal muscular atrophy, cystic fibrosis or fragile, X are targeted in this trial. It is estimated that everyone carries three to five recessive genes that could lead to serious diseases. It is only when both parents carry the same mutation that their child has a one-in-four risk of developing the corresponding genetic disease and a one-in-two risk of being a carrier.
The project is being carried out by the national research network, namely the Australian Genomics Health Alliance in conjunction with the University of Sydney, the Murdoch Children’s Research Institute in Melbourne and the University of Western Australia in Perth. The health professionals involved will inform parents about the test and the “options” available to them depending on the results. Couples with a high risk of having a child with one of these diseases can have access to in-vitro fertilisation followed by pre-implantation diagnosis to ensure that only “healthy” embryos are implanted. They can also decide to “conceive without IVF” and undergo prenatal testing or a test when the child is born, as early diagnosis of these conditions can lead to more effective treatment. They also have the option of embryo, sperm or egg donation. Pregnant women who are confirmed carriers may opt for diagnostic tests such as amniocentesis before considering abortion. Finally adoption is also offered, or couples may consider not having a child.
However, according to the protocol, “couples will only be told they have a genetic mutation if both individuals carry the same mutation for one of the diseases tested for”.
The Australian Department of Health has named this project “Mackenzie’s Mission” in memory of a baby girl born with spinal muscular atrophy who died in October 2017 aged seven months. It is part of the Australian Genomics Health Futures Mission which received a 500 million dollar investment from the federal government’s Future of Medical Research Fund. The Health Minister wants to offer pre-conception screening free of charge to all future parents to allow them to make “informed procreative choices”.
The Sydney Morning Herald (7/10/2018)