🧩UNDERSTANDING AND LOVE🧩

How do genetic and environmental influences give rise to autism?

Most appear to affect crucial aspects of early brain development. Many autism risk genes influence other networks of genes, increasing or decreasing their expression. Some appear to affect how brain nerve cells, or neurons, communicate with each other. Others appear to affect how entire regions of the brain communicate with each other. Research continues to explore these differences with an eye to developing interventions and supports that can improve quality of life.

Do vaccines cause autism?

Vaccines do not cause autism. It is possible that the timing of an autism diagnosis might coincide with the recommended vaccine schedule for children and adolescents. But scientists have conducted extensive research over the last two decades to determine there is no link between childhood vaccinations and autism. The results of this research is clear: Vaccines do not cause autism. Additionally, vaccination can protect children from many preventable diseases like measles.

The American Academy of Pediatrics has compiled a comprehensive list of this research.

Is autism genetic?

Research tells us that autism tends to run in families, and a meta-analysis of 7 twin studies claim that 60 to 90% of the risk for autism comes from your genome. If you have a child with autism, you are more likely to have another autistic child. Your other family members are also more likely to have a child with ASD.

Changes in certain genes or your genome increase the risk that a child will develop autism. If a parent carries one or more of these gene changes, they may get passed to a child (even if the parent does not have autism). For some people, a high risk for ASD can be associated with a genetic disorder, such as Rett syndrome or fragile X syndrome. For the majority of autism, multiple changes in other regions of your DNA  increase the risk of autism spectrum disorder. The majority of these DNA changes do not cause autism by themselves but work in conjunction with many other genes and environmental factors to cause autism.

If you or your child has ASD, we recommend that you explore genetic testing. Genetic testing could show you the genetic cause of you or your child’s autism and reveal any genetic mutations that might be linked to serious co-occurring conditions like epilepsy. Genetic testing can give doctors useful information so they can provide better, more personalized interventions. Read two family's stories on how genomics help their understanding of autism and receiving personalized healthcare.

What environmental factors are associated with autism?

According to the National Institute of Environmental Health Sciences, certain environmental influences may increase autism risk:

Advanced parental age

Prenatal exposure to air pollution or certain pesticides

Maternal obesity, diabetes or immune system disorders

Extreme prematurity or very low birth weight

Birth complications leading to periods of oxygen deprivation to the baby’s brain

Asperger syndrome, or Asperger’s, is a previously used diagnosis on the autism spectrum. It was one of five forms of autism defined by the DSM-IV. In 2013, Asperger syndrome and the other autism-related diagnoses were folded into the broader autism spectrum disorder (ASD) diagnosis in the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5), now the DSM-5-TR.

The previous autism diagnosis categories included:

Autistic disorder

Childhood disintegrative disorder

Pervasive developmental disorder, not otherwise specified (PDD-NOS)

Asperger syndrome

Rett syndrome

Although Asperger syndrome has been retired from use by medical professionals, some who received the diagnosis prior to 2013 still use the term and see it as an important part of their identity. Others prefer to refer to themselves as autistic. Both are correct; it is just a matter of personal choice.

Asperger syndrome symptoms

There is significant overlap in Asperger’s symptoms and ASD symptoms. Learn more about the symptoms of autism.

What is Asperger's called now?

Today, those who would have previously met the criteria for Asperger syndrome are diagnosed with level 1 ASD. There is no difference between Asperger's and autism level 1 diagnoses.

Learn more about level 1 autism and how it is diagnosed in the DSM-5-TR.