Our charity has stated definitively, for the first time, that autism is genetic, after a robust and comprehensive review of high-quality research into this subject.

This work is important in light of the daily challenge of false claims about autism in the media and politics in the UK and the US, which are spreading harmful lies and distracting from the very real issues autistic people face.

The review

Our charity’s research team looked at all the evidence about what causes autism, analysing 83 number of research papers. This showed:

• Autism is genetic. You’re born autistic and you’re autistic for life. Most autistic people are autistic because of genes they got from their parents. This is why autism often runs in families.
• Much less commonly, other factors can play a role, but usually in combination with genes from parents.
• There isn’t a single ‘autism gene’. Thousands of genes combine to make a person autistic. Scientists have identified many of these genes, but they think there are still many more to find.
• There is no genetic test for autism. We don't fully understand how genes combine to make a person autistic. It is complex and no simple test can give an accurate answer.
• Genetic testing cannot predict whether a child will be autistic or not, and it can’t be used to diagnose someone as autistic.

What autistic people say

We shared our review with a panel of 300 autistic people and family members. The majority (64%) felt this information would help dispel myths about the causes of autism, but many expressed concern that this could lead to parental guilt or blame.

We all have a desire to be understood, valued for who we are, and to make the most of our talents. But autistic people often feel judged. One in four autistic people say that when they tell a member of the public they are autistic, they usually get a negative reaction. Autistic people are three times more likely to die by or attempt suicide than non-autistic people, and nine in 10 autistic people (90%) experience poor mental health due to attitudes or perceptions of autism.

Autistic people and their families told us they want future research to focus on autistic priorities, rather than more genetic research or ‘cures’. They also want us to ensure that the positive aspects of autism and the strengths it brings for some people are emphasised. We’ve included answers to the questions they raised with us on our Causes of Autism page and will continue to listen to what they tell us.

Kelly-Marie

Kelly-Marie, from Birmingham, says: " In my family, it's obvious that autism is genetic. I see it in my siblings, children and possibly myself as I go through the assessment process.

"For us, knowing it is genetic isn’t a bad thing because it explains to us why we share a unique way of processing the world around us. It shows that autism is simply a fundamental part of who we are and seeing it as genetic helps shift the conversation away from outdated blame- like “bad parenting”- and toward understanding brain diversity. Awareness and acceptance of the genetic basis allows focus on creating environments where neurodivergent people can thrive.

"It can be a relief that nobody has done anything “wrong” and it makes me feel more connected to my siblings and children sharing the same brain chemistry."

Our comment

Dr Judith Brown, Head of Evidence and Research at the National Autistic Society, said: “The National Autistic Society has carried out a robust and comprehensive review of high-quality research.  As a result, we can definitively state, for the first time, that autism is genetic. Our review of the research evidence was carried out in response to the daily challenge of false claims about autism in the media and politics, which distract from the very real issues autistic people face.

“Autism is genetic. You are born autistic and are autistic for life. Knowing that you’re autistic can be life-changing. It can help you make sense of feeling different and give you strategies to manage the things you find hardest.

“My sincere hope, plea and wish is that people read our advice and guidance, take on board the evidence, and that we can move to focusing on what really matters and will make a difference for autistic people. This must be focused, sustained changes across education, health and social care, improved assessment and diagnostic services and better mental health support to create a society that truly works for autistic people.”

Our research process

We have a dedicated evidence and research team who review all the published evidence on a topic and judge it against recognised quality assurance criteria. We say when the answer isn't clear. When it is clear, we can be confident that our statements are backed by an audit trail of quality evidence.

Further information

Read our blog about the new evidence review.

Find out more about autism.

Read more about what causes autism.

Find out more about our research work.

Read more about our work to challenge misinformation.