Push for more genetic screening for prospective parents

Prospective parents are being encouraged to undergo a simple test that could reveal genetic dangers before starting a family.

Every single one of us is carrying some sort of genetic mutation and now experts are advising all prospective parents to consider genetic screening before starting a family.

One in 25 people of caucasian descent carry the gene for cystic fibrosis, those of Mediterranean heritage — and one in 10 of South East Asian descent — are more likely to carry thalassaemia, which leads to severe anaemia, while one in 35 are thought to carry the recessive gene that causes spinal muscle atrophy, the biggest genetic killer of infants under two.

However, it is not until you match with a partner who has the same gene mutation that offspring will be affected.

Rachael and Jonathan Casella with their new baby Izaac who was born via IVF and genetic screening. Picture: Sam Ruttyn

Mackenzie Casella died of SMA in 2017 aged seven months.

New guidelines for general practitioners encourage all prospective parents, as opposed to previous guidelines based on only those with a family history, to have a simple blood test to screen for genetic mutations.

“Getting the message out to families and GPs about screening is so important,” Rachael Casella of Mackenzie’s Mission said.

“Especially because many GPs don‘t realise the guidelines have changed and that everyone should be offered screening now, not just those with a family history.

“So many medical professionals are unaware the guidelines have changed.”

Rachael and Jonathon Casella set up Mackenzie’s Mission after their daughter Mackenzie passed away at just seven months of age in 2017. Both her parents carried the recessive gene for spinal muscular atrophy.

The Casellas launched a campaign in 2018 calling for reproductive genetic carrier screening to be routine and free for all prospective parents in Australia. In addition, a study is midway through recruiting 10,000 couples and will screen for more than 750 genetic conditions.

The couple has just given birth to their new baby boy Izaac after using genetic screening and IVF themselves to ensure he did not carry the gene.

“We all carry defective genes and it can happen to anyone and it comes down to luck when you get together to have children,” the mum said.

Sarah and Carmelo Cisca and sons Joseph and Christian. Joseph inherited cystic fibrosis and Cristian was conceived with IVF to be sure he didn't. Picture: Sam Ruttyn

When Sarah and Carmelo Cisco of Croydon Park met, neither knew they each carried the recessive gene for cystic fibrosis (CF).

They had a one in four chance of giving birth to a child with the condition, which can lead to lung failure and premature death.

When Joseph was born three years ago, his condition was identified through the newborn baby screening program.

“Two random people meet, get married, have a baby and find out on that both sides we are carriers of the gene, it was a shock for everyone,” Sarah Cisco said.

“It turns out all of our siblings are all carriers of the gene.”

Sarah and Carmelo Cisca and sons Joseph and Christian. Picture: Sam Ruttyn

The couple chose genetic screening and IVF to avoid the 25 per cent risk of having another child with cystic fibrosis.

“We felt it wasn’t fair to bring another child into the world that has CF as well,” Mrs Cisco, 30, said.

Of her six embryos, four did not carry the gene and two were carriers. Nine months ago, Christian was born free of any CF genes.

“It is quite expensive, about $25,000 (for the full IVF round) and some aren’t as fortunate as us, our parents helped us to afford IVF,” she said.

“I know some CF mums who can’t afford it so they decide to go naturally and cross their fingers or don’t reproduce again.

“I feel as a young married couple embarking on a family, if we could have tested for things like CF ... I feel if it was available we would have done that.”

Dr Manny Mangat, fertility specialist at IVF Australia Vitus Health, said many couples doing IVF now want genetic screening.

“It is devastating when couples unexpectedly have an affected baby with a condition they did not know they carried,” Dr Mangat said.

“I routinely offer genetic screening to couples but at the moment is it expensive because there is no rebate for that testing.”

The Mackenzie’s Mission Research project is the first large-scale study to look at the benefit and cost-effectiveness of widespread screening.

“My dream is that screening is offered to all Australians for free,” Mrs Casella said.

Virtus Health is collaborating with Mackenzie’s Mission support them through one IVF cycle with genetic screening to screen for a healthy embryo.