Adults urged to get pre-pregnancy genetic screening

Melissa and John Grigsbey had just taken their newborn daughter home when there was a phone call. Something wasn't quite right.

It had been three days - or maybe four.

"We were so thrilled to have her home," Melissa Grigsbey says. "She was the first grandchild on my side and the second on my husband's side of the family."

The result of a routine test for newborns was yet to arrive. That day, thankfully, the new mother had a friend over.

"I got a phone call from the hospital saying her heel-prick test had come back. Georgia had cystic fibrosis," Melissa says. "I had heard of it, but I actually didn't know what it meant. I had no idea, no clue."

Brigid Flanagan from Cystic Fibrosis Community Care says 94 per cent of babies with cystic fibrosis are born to parents with no prior family history of the disease.

"Most people are blindsided when their baby is diagnosed," Flanagan says.

The organisation, and others like Spinal Muscular Atrophy Australia, have urged prospective parents to get pre-pregnancy screening to see if they may be carriers of such recessive genetic disorders.

Recessive disorders go undetected, as they do not cause any symptoms in the carrier.

Like their counterparts in the US, the Royal Australian and New Zealand College of Obstetricians and Gynaecologists are also recommending informing healthy adults about gene carrier screening before conception.

The college is preparing new guidelines for health practitioners detailing how to navigate the complex consultation that can deliver heartache and moral dilemmas.

Professor Steve Robson, president of the college, says it is a conversation that needs to be had.

"It's now clear with the advances in genetic screening that patients should definitely be made aware that carrier screening is available," Robson says.

"The critical thing, if you are going to offer screening, is the counselling.

"It is not like other tests in pregnancy where you just write a form. It is an incredibly complex test with a lot of implications."

Though not available on Medicare, the testing itself is not complicated, and costs up to $600.

Usually a swab taken from inside the cheek or a blood sample reveals within weeks the genetic lottery we all carry - the gene mutations or changes in our DNA.

One in 25 Australians carry the cystic fibrosis gene. As in other recessive conditions, it takes two to pass the disorder to the child.

So when two carriers meet, fall in love and decide to have a baby, they create a one-in-four chance of having a child with the life-threatening disorder.

A swab taken from inside the cheek can reveal within weeks the genetic lottery we all carry.

A swab taken from inside the cheek can reveal within weeks the genetic lottery we all carry. Photo: Ken Irwin

Nigel Laing, who hunts human disease genes at the Harry Perkins Institute of Medical Research in Western Australia, says each of us is carrying three to five severe recessive diseases. We just don't know what they are, ????yet.

Cystic fibrosis is caused by mutations in the CFTR gene, which tells the body how to control the salt and water balance in the lungs and other tissues. Advances in treatment have increased life expectancy of those affected to 37 years.

Now 19, Georgia spends hours clearing her lungs of mucus just so she can breathe. Repeated physiotherapies and taking 35 tablets are daily realities of her life.

Melissa Grigsbey says she blames herself for Georgia's suffering.

"Because I know that it has come from my husband and I, I do feel responsible that she's got to go through all that," she says. "And I often think it is so unfair for her because they don't get to choose."

Laing says everyone should be given the gift of knowledge.

"We should have pre-pregnancy carrier screening so that couples know they are at risk instead of finding out ... by having an affected child," he says.

"I have been involved in diagnostic laboratories for ??? 30 years. For example, Duchenne muscular dystrophy [a progressive wasting of the body's muscle tissue]: two-thirds of the mums of the affected boys are carriers.

"And every time we diagnose a boy with Duchenne whose mother is a carrier, I wish we had found the carrier first so then she would be in the same position as a known family."

He says those who have a family history of a disorder have choices.

"Couples, who know they are at risk because they already have an affected child, they can ??? test the pregnancy and see if the unborn child is affected," Laing says.

"You can also have pre-implantation genetic diagnosis, but that means going through IVF and testing the embryos before you implant them.

"They can decide to abstain from having children or [have a] sperm donation."

When Georgia was a toddler, Grigsbey fell pregnant again. This time the family was prepared. Tests revealed Alexander, now 16, was a carrier. Another boy followed, Samuel, now 11, completely free of the disorder.

Parents who are carriers can access IVF for pre-implantation genetic diagnosis.

Parents who are carriers can access IVF for pre-implantation genetic diagnosis.

"We didn't know IVF was an option when we had Alex. Sam just came along; we weren't planning on having another child," Grigsbey says.

"We wouldn't be without any of our three children ??? [but] pre-pregnancy carrier screening gives you the opportunity to say 'well, this is the decision I am making that's right for me'.

"I don't know what we would have done, but I think it's better to go into something knowing."

A global issue

Globally, mass-screening programs in groups with a history of genetic disorders have been known to reduce occurrence of certain diseases. This includes Tay-Sachs disease causing dementia in children, leading to their death by the time they are three or four years old.

Laing says the long-term screening program in the Ashkenazi Jewish population around the world reduced the instance of the disease in those communities by more than 90 per cent.

"The most comprehensive ??? population-wide ??? pre-pregnancy carrier screening program is in Israel," he says.

"They screen 60 to 70,000 people a year for about 100 recessive diseases."

Laing says anecdotal reports suggest the screening program has reduced the incidence of a lot of those diseases in Israel.

Some Mediterranean countries which have a screening program for thalassaemia, a disorder that causes severe anaemia, have also seen reduction in affected children, he says.

Yet pre-pregnancy screening is not a silver bullet - a cure-all magic formula for a healthy child.

Laing says screening doesn't guarantee an unaffected child because not all disease-causing mutations in genes have been identified.

Then there are chance errors in DNA replication which result in a child being born with a disorder even though neither parent is a carrier.

For Dr Felicity Boardman, who focuses on social and ethical aspects of medicine, the problem is not the disorders, but our attitude towards disability and illness.

Boardman, an assistant professor at Britain's Warwick Medical School, says her research on families living with disorders such as thalassaemia, fragile X syndrome and cystic fibrosis shows their ambivalence towards pre-pregnancy carrier screening.

"These people live closely with genetic conditions every day, and while the difficulties associated with this should not be under-estimated, many still asserted that having their condition enriched their lives in particular ways," Boardman says.

"There wasn't an overwhelming sense that these people felt short-changed in some way by the lottery of life. Rather, their accounts highlight that we need to question the inherent assumption that is right at the core of the drive towards pre-pregnancy screening: that having a genetic disease is always a tragedy to be avoided. Because for those people who know what it's like to live with better than anyone else, it's not always the case.

"We have to think of the direction our society is taking, the ideas we are perpetuating, that it would be better to be non-existent than to have a genetic condition."

She says despite advances in technology, pre-pregnancy screening can't predict diseases like mental illness or a tendency to alcoholism.

"Pre-pregnancy carrier screening will change the way we view reproduction ??? creating a best possible child who is going to have the best possible chance," Boardman says.

"Yet genetic disease is one of many difficult things that can happen in people's life."

John Christodoulou, a professor of genomic medicine at Murdoch Children's Research Institute, says suffering can only be minimised, never removed completely.

He says thanks to advances in genomic sequencing technology ????- the ability to read and analyse the genetic code in one hit - identifying new disease-causing genes has become faster and more cost-effective.

Christodoulou says it is the most important technology of this decade, set to transform the way health care is delivered.

In the movie <i>Gattaca</i>, parents chose the genetic traits of their children to ensure perfection.

In the movie Gattaca, parents chose the genetic traits of their children to ensure perfection.

Its aim, he says, is to restore reproductive confidence, prevent and treat disease, not to create perfect babies.

"As a medical geneticist ??? I am not advocating that this technology is going to put us into a Gattaca [a 1997 American science fiction film] situation where people will only accept the absolute perfect individual and everyone else is deemed to be 'sub-optimal' or 'imperfect'," Christodoulou says.

"We are about treating and preventing specific diseases rather than creating a superhuman."

Professor John Christodoulou: 'We are about treating and preventing specific diseases rather than creating a superhuman'.

Professor John Christodoulou: 'We are about treating and preventing specific diseases rather than creating a superhuman'. Photo: Peter Casamento

He says any technology - if used effectively and in a responsible and ethical way - can only benefit humankind. Advances in genomic testing have increased the diagnostic rate for intellectual disabilities by about 50 per cent.

Deborah Schofield, professor of health economics at the University of Sydney, is working on the economic evaluation of genomic medicine.

Along with the NSW Genetics of Learning Disability Service, she is in the early stages of research into the cost-effectiveness of the use of whole-genome sequencing to diagnose intellectual disability in families.

Their Economic and Psychosocial Impacts of Caring for families affected by Intellectual Disability (EPIC-ID) study is examining the potential economic benefits of preventing and treating intellectual disabilities.

"We will look at economic impacts of improvement in health in the case where there is a treatment, and in a small number of cases there are therapies, but also in terms of family planning," Schofield says.

"What we found in the part of the sample that we analysed is that the cost for families with a young adult with intellectual disability over 10 years now is about $1.75 million."

She says apart from the financial costs, there is also a serious toll on the physical and mental health of the carers.

Taking a different path

Growing up, Patti Ruby saw the effects of fragile X syndrome, passed on through the mother, on her beloved late uncle,a cousin, a nephew, and her older brother.

The genetic condition causes intellectual disability, behavioural and learning challenges, and is also the most common single-gene cause of autism worldwide.

At 12, Ruby decided she would not bring another fragile X carrier into the world.

So when she became pregnant with a child with the disorder, she had no hesitation in obtaining an abortion.

"Growing up I saw the frustrations, I saw the lack of understanding, compassion," she says. "It's not that I couldn't love the child, I just didn't want that responsibility."

 Simon and Patti Ruby with their children, Connor and Mia, when they were younger.

Simon and Patti Ruby with their children, Connor and Mia, when they were younger. Patti, who is a fragile X carrier, says she didn't want her children to go through what she did. Photo: Supplied

Her first child, daughter Mia, now 19, was not affected by the disorder nor was she a carrier.

Two years later, Ruby fell pregnant again. This time testing at 12 weeks revealed the foetus - a girl - was a carrier.

"That was a difficult choice," she says. "I decided not to have a child that was a carrier, because I was a carrier. I didn't want her to go through the struggles that I was going through."

Another pregnancy followed, this time a baby boy who would be heavily affected by fragile X syndrome.

Despite it being a more clear-cut decision, the termination at 18 weeks left Ms Ruby grief-stricken and in need of counselling.

The Queensland couple travelled to Sydney to try IVF and pre-implantation genetic diagnosis, but fell pregnant naturally.

Ruby again underwent a procedure at 12 weeks to abort another boy who would have developed fragile X syndrome.

Difficult choices: Patti and Simon Ruby with Mia, 19, and Connor, 13.

Difficult choices: Patti and Simon Ruby with Mia, 19, and Connor, 13. Photo: Supplied

Finally, in 2003, they had a healthy child, Connor, now 13, through IVF.

Ruby says that though she had support, there was some judgement too.

"I was accused of playing God," she says. "People are going to have their own opinion about everything, but they are not making the decision that I have to make with the cards that I was dealt."

This story Adults urged to get pre-pregnancy genetic screening first appeared on The Sydney Morning Herald.