Autism and Noonan Syndrome

Brett | Feb. 18, 2021


Autism Spectrum Disorder (ASD) is a lifelong developmental disability that affects how people behave and interact with the world around them. It may be mild, moderate or severe. The main features of autism are difficulty in social interactions and communication, and restricted and repetitive behaviours and interests. Children or adults with autism may be highly intelligent, of normal intelligence or have learning difficulties.

About 1 in 150 Australians are affected by autism and symptoms are present in infancy but may not be noticeable until the age of two or three years and in some people the diagnosis comes much later in life.

ASD occurs at a higher rate in individuals with Noonan Syndrome (NS) than in the non-NS community.

Symptoms of ASD

All children develop language, communication and emotional skills at different times. But, for a child with autism, this development is seriously impaired and has a significant impact on their lives.

Parents may notice that their child’s behaviour is unusual in the first few years of life. Early signs may include delayed speech, repetitive behaviours such as rocking or twirling, or spending hours focusing intently on one thing. Children with autism may lack interest in playing with other children, and in severe cases may show no interest in the surrounding world at all.

The behaviours associated with autism fall into two broad areas: impaired social interaction and communication, and restricted and repetitive behaviours and interests. For some children the symptoms and impairments are mild, but others exhibit severe autistic behaviours.

The common signs and symptoms of autism are:

  • lack of social or emotional exchanges like pointing, smiling and showing you things
  • lack of non-verbal communication such as nodding and shaking head, using hand gestures
  • difficulty in developing and maintaining relationships appropriate to the age, such as peer play, lack of close friends
  • delayed expressed speech and understanding of speech
  • lack of eye contact when speaking
  • loss of language skills at any age
  • excessively following routines, patterns or behaviour, and becoming distressed at changes
  • stereotyped or repetitive speech, movements or use of objects, such as rolling wheels before eyes, flapping hands, toe walking
  • strongly reacting to sensory input such as sound, pain or textures
  • restricted or fixated interests such as only playing with certain toys or discussing certain topics
  • being aggressive toward other people or toward self


It can be stressful and worrying for parents to learn that their child has autism. But the earlier a diagnosis is made, the sooner the best support and treatments are put in place to get the best outcome for your child.

Some parents are understandably reluctant to procure an ASD diagnosis for fear of their child being ‘labelled’ or attracting stigma or the negative social implications of such a diagnosis. The NSAA encourages all parents with children with suspected ASD to pursue prompt diagnosis as this will allow access to government funding for support and treatment services as well as facilitate more effective teaching and social strategies for their class, school and work experiences.

Here are some of the key reasons why we so strongly encourage parents to seek answers as soon as they start to have concerns that their child might have autism:

  • A diagnosis gives access to funding
  • Teachers and schools will have information that will allow them to more effectively support your child
  • Your child will be entitled to accommodations and disability provisions (if needed).
  • You will gain a better understanding of how your child processes the world.
  • Your child will understand themselves better and know that they are connected to a larger group of people on the autism spectrum.
  • Not surprisingly, the vast majority of parents of children with an autism diagnosis wish that they had received answers even earlier.
  • Finally, even if your child is assessed and is NOT diagnosed with autism, a robust assessment process still has immense value: it can help reveal the specific reasons for a child’s challenges and the most effective support for them.

A diagnosis is usually made by a qualified specialist, such as a paediatrician, or via a comprehensive assessment performed by a team of specialists. This may include a paediatricianpsychologist or psychiatrist and sometimes a speech pathologist. The specialists will meet and watch the child to assess his or her communication skills, ability to interact socially and general behaviours.

Clinicians use a set of standard tests to make a diagnosis. They will see if the child has certain behaviours and social responses.

The umbrella term ‘autism spectrum disorder’ (ASD) now describes all levels of autism, from those individuals requiring support (level 1), those requiring substantial support (level 2) and those more severely affected and requiring very substantial support (level 3).

Children can usually be diagnosed at around two, but sometimes symptoms are subtle and children are not diagnosed until they start school or even until they become adults.

If your child is diagnosed with autism there are many various treatment options.

Research shows that the earlier a child is diagnosed and intervention implemented, the more likely it is they’ll develop the communication, social and life skills needed for a good quality of life.

Boys are 4 times more likely to diagnosed with ASD than girls but this does not mean ASD affects boys disproportionately. There are many reasons to believe girls with ASD are significantly underdiagnosed compared to boys as their symptom profiles tend to more subtle. Girls with ASD are more likely to engage in imaginative play and their communication and social skills are stronger than their male ASD peers which can lead to non-diagnosis.

ASD & Noonan Syndrome

There is a 15-30% prevalence of autism in NS. This is not surprising given genome analysis has shown the RAS/MAPK pathway is involved in autism and mutations in this pathway are responsible for Noonan Syndrome. This is significantly higher incidence of ASD than in the non-NS population (1.5%).

The higher prevalence and severity of autism traits in RASopathies compared to unaffected siblings suggests that dysregulation of Ras/MAPK signalling during development may be implicated in ASD risk.

No significant difference in IQ has been noted between NS individuals with ASD and without ASD, indicating social impairments in NS may be more ASD related than due to cognitive deficits.

Screening for ASD should be undertaken for all children with NS and should be considered whenever a child with NS presents with behavioural, social or relationship difficulties.


To date there has not been a single, definitive scientific explanation for the cause of autism. We do know the RAS/MAPK pathway is involved which explains the higher prevalence of ASD in NS as described above. There are over 133 genes identified with autistic behaviours so there will be never be one singular biological cause.

Environmental factors (most likely during prenatal development) are also thought to contribute to autism. This makes inherent sense when you realise that most disorders/diseases are a mixture of genetic susceptibility/function and environmental influence. One study which highlighted prenatal environmental influence found fraternal twins have a 30% chance of having autism as opposed to 10-20% of non-twin siblings. Genetic inheritance of autism was also evident by another twin study which showed a 90% correlation of autism in identical twins.

It can be tempting to assign causation or blame to singular issues but autism is a complex, multi-factorial disorder with many causative factors.


Depending on how severe the autism is, caring for a person with autism can be a lifelong commitment for parents and carers. Specific symptoms and social skills can be improved with the right support and programs, and the best outcomes are achieved with early intervention.

Treatments used to manage autism are best started as early in a person’s life as possible. Ideally a diagnosis is made early in a child’s lifetime. Because every child with autism is different, the best results are obtained from a treatment program specifically tailored to a child’s individual needs.

Language and social skills are taught through intensive educational programs and behavioural therapies. Speech pathology focuses on developing communication and social skills. Occupational therapy concentrates on sensory motor development, such as learning play and fine motor skills, as well as how to cope in social situations.

Sometimes claims are made about treatments that are misleading. Avoid treatments that offer a ‘cure’ or ‘recovery’ as there is no evidence to support these claims. Ensure that the treatments and supports you choose are informed by evidence.

The NSAA recommends always consulting your paediatrician before commencing any therapy or treatment schedule to make sure it is evidence based and won’t risk your child’s health.


Public and private schooling options are available for children with autism. Your child with disability has the right to go to a mainstream government, independent or religious school, regardless of their level of disability. They might also be able to go to a government or independent special school. You can decide which option you think is best for your child and your family.

There is very useful information in regards to schooling at the Autism Awareness website.

If your child has been diagnosed with autism they will require assessment to determine their educational needs which can facilitate the most effective school experience for them and their learning.

Individualised Education Plans (IEPs) can be organised with your school and should be collaborative, comprehensive and address all their educational needs. The IEP should include educational goals and outcomes and detail the support your child will receive.


In Australia, the unemployment rate for autistic people is 31.6%. This is three times the rate of people with disability, and almost six times the rate of people without disability.

Research has revealed that more than half of unemployed autistic Australians (54%) had never held a paid job, despite often possessing the skills, qualifications and a strong desire to join the workforce. More than half of employed autistic Australians would like to be working more hours and given a more challenging role, with 45% reporting that their skills are higher than required in their current job.

These statistics are worrying for parents and caregivers of individuals with ASD but with the right support Autistic individuals can find, gain and maintain paid employment. Social workers, Psychologists and Occupational Therapists can help people with ASD navigate the workforce and workplace and give them skills to mitigate and reduce the ways in which their symptoms may impede their productivity and careers.  There are many providers on the NDIS who provide employment support programs.

But to make a significant dent in the unemployment rate for people with autism, states need to establish large collaborative programs involving schools, vocational rehabilitation services, counsellors and local businesses. There are many roles and tasks that people with ASD can complete with greater accuracy and speed than non-ASD employees (particularly in data and inventory management, IT services, manufacturing and design).


A diagnosis of ASD can be frightening, overwhelming and saddening, particularly when coupled with a diagnosis of Noonan Syndrome. It is important to seek help, advice and counselling to ensure you can help your loved one with NS and ASD as best you can and also remember to be sure to look after yourself and your personal needs too.

There are many amazing things individuals with ASD can accomplish if they have the appropriate emotional, educational and workplace supports.




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