Is Autism Genetic?

Is autism genetic or hereditary?

Families often ask whether autism is inherited. Genes are a big part of the picture, and the figures below come from the Autism Association of Australia (Autism Association of Australia).

Our guide to what causes autism looks at the wider question of causes and what is still being studied.

Is autism genetic if it is passed down in families?

Autism can be passed down in families, but a family pattern does not let anyone predict whether a particular child will be autistic. A specialist is the right person to explain what a family history means for you.

• Can autism be passed down genetically? Genes play a large part, which is why the chance of another autistic child in the same family is estimated at around 1 in 5.
• Is autism genetically inherited every time? No. Around 1 in 5 is an estimate of chance, not a certainty, and genes do not explain every case.
• Siblings: brothers and sisters may be alike or quite different, and each person’s strengths and support needs should be understood on their own terms.
• Adults wondering about themselves: if you recognise autistic traits in yourself, your GP can talk with you about an adult assessment.

If you are an adult asking this question, our guide on autism and neurodiversity explains how families can think about difference.

Is there an autism gene? Chromosomes, X and MTHFR

You may read about one particular gene or chromosome being linked to autism. These names come up often online, so here is how to read them carefully.

• Is there an autism gene? The evidence points to genes having a strong influence overall, rather than one gene that explains autism for everyone.
• Chromosome 15 and the X chromosome: you may see claims about these, and a genetics service can explain whether any finding applies to your family.
• MTHFR gene mutation and autism: online articles link MTHFR to autism, but a test result on its own cannot diagnose autism or tell you what supports to use.
• Genetic testing: ask your GP or paediatrician whether testing is relevant for your family, and what a result could and could not tell you.
• Cautions: be wary of supplements or treatments sold on the basis of a gene result, and speak to your GP before changing anything.

TQN Care support workers help with personal care, community access, respite and help around the home across Sydney, Melbourne and surrounding areas (NSW & VIC). Tell us what you need and we will call you back.

Is autism a genetic disease or something else?

Many autistic people and families do not think of autism as a disease. They describe it as a different way of experiencing the world, with strengths as well as support needs.

• Genetic disease: this phrase suggests an illness that needs treating, and many autistic people feel it does not describe their lives.
• Genetic condition: if a family has been told about a separate genetic condition, a specialist can explain how it relates to autism for that person.
• Mental health: our guide on whether autism is a mental illness explains the difference.
• Other factors: because genes do not explain everything, other influences are still being studied, and our causes guide covers what is known.

Is autism genetic when other conditions run in families?

Doctors often ask about family history during an assessment, including other conditions in the family.

• ADHD: the Australian ADHD Guideline found children and adolescents with autism have a significantly higher risk of ADHD (AADPA). Read about whether ADHD is hereditary or genetic.
• ADHD in families: the same guideline says ADHD is highly heritable in children and adults, with heritability estimated at 70–80% (AADPA).
• Epilepsy: the guideline also lists epilepsy among the groups with a higher risk of ADHD, and our guide explains whether epilepsy can be genetic.
• Telling the doctor: mention any autism, ADHD, epilepsy or other diagnoses in the family so the assessment has the full picture.

How to find out more about autism and genetics in Australia

If you want to explore the question for your family, these steps are a sensible path.

1. 1Write down your family history. List relatives with autism, ADHD, epilepsy, learning differences or developmental concerns so the doctor has the full picture.
2. 2Book a GP appointment. Ask whether a referral to a paediatrician or genetics service makes sense for your situation.
3. 3Ask what a test could change. Find out whether results would affect your child’s care, supports or planning before you decide.
4. 4See a genetic counsellor if offered. A counsellor can explain what findings mean for you, your children and extended family.
5. 5Call Autism Connect. Autism Connect on 1300 308 699 is a free, national autism helpline, open 8am to 7pm Monday to Friday (Amaze).

When to talk to a GP or specialist

You do not have to wait for certainty before you ask for support. These are good reasons to make an appointment.

• A child has differences in speech, play, eye contact or sensory reactions that you want to understand better.
• Autism, epilepsy or a genetic condition runs in your family and you are planning a pregnancy or have concerns about a child.
• A child has lost skills they previously had, such as speech or social interest, and you want to have this checked.
• You have seen a genetic test or supplement advertised for autism and want independent advice before spending money.
• You are an adult who recognises autistic traits in yourself and want to explore assessment.

Call 000 in an emergency.

TQN Care support workers help with personal care, community access, respite and help around the home across Sydney, Melbourne and surrounding areas (NSW & VIC). Tell us what you need and we will call you back.

Your next step

Whatever the cause, support depends on what a person needs day to day. TQN Care provides support workers for personal care, community access, respite and help around the home, and we work with families to match support to routines and goals. Browse our TQN Care NDIS services, or read our guide to NDIS funding for autism to see how plans work if you meet the NDIS access requirements.