Am I autistic? NZ researchers say DNA testing may offer Kiwis firmer answers

When Tabitha Knight, 38, looked back, she realised she’d taught herself how to “mask” her own differences around others.

“I thought I was just learning how to do life… learning how to ‘people’,” the Hutt Valley resident recalled.

“I wasn’t actually aware that this just came instinctively for other people and that the cognitive load was so much less for them.”

The three women are among a rising number of Kiwis who’ve learned they’re autistic in adulthood.

“Everything changed for the better after I received my diagnosis,” Woodfine, who works as an entertainer for children’s parties, said of being diagnosed in her early 30s.

“It was a humongous weight off, and I was like, ‘Okay, so this is why I am that way I am’.”

For Knight, she figured it’d be helpful for her children, who are also autistic.

“I didn’t feel any immediate need to find out… but I always thought that, if I am, it’d be quite nice for my kids in the future, just helping them [to] identify and explain.”

What is autism?

Autism is a neurodevelopmental condition that changes the way people see the world and interact with others.

While challenges with sensory needs, social skills and executive functions might be commonly reported, no two autistic people are alike – nor is there a single shared experience of autism.

Advocates are similarly at pains to point out it’s not a mental illness – or something that needs curing – and that too many autistic people continue to face misconceptions and stigmas.

In New Zealand, one recent survey found just one in five said society generally accepted them as autistic people – while nearly half said they felt that way sometimes.

It’s not known just how many Kiwis are autistic: around 1.6% of the population self-reported in the last New Zealand Health Survey, but that’s almost certainly an under-estimate.

All the while, wait lists for diagnosis in the public system are growing.

“The increase appears to be both in children and adults,” said Larah van der Meer, research and advocacy manager for Autism New Zealand, which offers its own diagnostic service.

“Typically, a diagnosis wasn’t considered when the adult was a child, but now there is more awareness and understanding, adults recognise traits in themselves and want confirmation through a diagnosis.”

In New Zealand, she adds, that isn’t straightforward.

“The only way to get a diagnosis through the public system is through the mental health service, which then requires a co-occurring mental health condition, and it varies between regions whether this is even possible.”

As a result, most adults must pay to get a diagnosis privately, which can cost upwards of $1500, and has been creating equity barriers for low-income families.

For children, meanwhile, concerns remain that families are waiting too long for diagnosis through the public system.

One recent New Zealand study found the average age of diagnosis was 6.6 years – around three years after parents first suspected their child was autistic.

The genetics of autism

This month, University of Auckland researchers reported an approach they say might make the diagnostic process more conclusive – and cheaper.

It’s genomic sequencing – decoding a person’s genetic make-up – searching for more than 100 specific genes that have been identified to cause autism.

While a genetic cause can’t always be found, overseas studies have found these genes in a notable percentage of individuals.

When the researchers took that approach in New Zealand for the first time, sequencing around 200 autistic people and 100 non-autistic family members, they found variations in genes known or likely to cause autism in around a third of the participants.

Study author Dr Jessie Jacobsen said the approach was shown to be successful for people regardless of their neurological differences and age.

As some of the gene variants were linked with co-occurring conditions, or medical challenges in later life, finding them with DNA screening might enable targeted monitoring and management earlier.

Moreover, it could end a family’s long search for an accurate diagnosis, as it did for some in the study, and help people find their community through support groups.

“Most individuals and their families were just really stoked to have the opportunity to solve the puzzle, and get a really specific diagnosis,” said study lead author and PhD student Suzanne Musgrave.

University of Auckland child psychiatrist Dr Hiran Thabrew said New Zealand, with its under-resourced public health services, was still “nowhere near” personalising care for autistic individuals with genetic testing.

“However, understanding genetic profiles and their clinical associations are vital steps on the journey.”

Van der Meer certainly saw a role for it – whether confirming a diagnosis without the need for a full assessment, or when an assessment was inconclusive.

“It could also provide efficiencies and speed up the diagnostic process and, with so many people seeking and waiting for a diagnosis, this is important,” she said.

“The greatest challenge at the moment is that there isn’t enough funding for people to access genetic sequencing.”

Meanwhile, there remained a wider need for current diagnostic tests to be more accessible for Kiwis who wanted them.

“I’m a big advocate for people doing it, or at least getting on the waitlist, early if they feel they’ve got that curiosity,” Knight said.

“Because you never know when it’s going to start grating at you.”

Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology. His children Harry, 8, and Theodore, 6, are autistic.

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