Is Autism Hereditary? Explaining Autism Genetics

Over the past several decades, the causes of autism spectrum disorder (ASD) have been widely discussed. Many people, experts included, believe that ASD results from environmental causes or habits of the mother in utero. Even certain vaccinations have fallen into the realm of blame.

But the reality is that an ASD diagnosis can be a result of genetics, though the genetic signature responsible for the majority of ASD cases is still unknown. Sometimes it can be as simple as someone in your family having ASD, no matter how distanced they might be on the family tree, but not always.

So, if you've found yourself wondering whether autism is hereditary, genetics do play a key role. Read on for more about how genes impact the development of autism.

Autism Spectrum Disorder (ASD) Explained

While ASD is something you're born with, it's actually considered a developmental disorder. It includes a broad range of conditions, hence the name autism spectrum disorder. Many people with ASD have challenges with social skills, repetitive behaviors, speech, and nonverbal communication.

ASD affects people in different ways and to varying degrees. Some people on the spectrum need little or no support in their daily lives, while others might need much greater support. Much of the time, gene mutation and expression as well as certain environmental factors determine where someone falls on the autism spectrum.

Is Autism Hereditary? A Closer Look at the Causes

The exact cause of ASD is not always easy to pin down from one person to the next. There are a few factors at play that impact a child's risk of developing autism. But at the top of this list is genetics. Researchers are still looking for the exact genetic signature to fully characterize autism as genetic, but they are getting closer every day.

In short, autism is hereditary. But there are other risk factors that can play into its development, such as biological and environmental factors. These causes merely contribute to the likelihood of ASD; they are not the primary reason a person might develop autism.

Some of the most common risk factors for autism, in conjunction with genetics, include:

• A child born to older parents
• Serious infections during gestation
• Birth difficulties
• Exposure to certain environmental toxins
• Premature birth

What the Twin Studies Show

Some of the most compelling evidence that autism is hereditary comes from twin studies. Since the first major autism twin study, several others have followed. All of the results show that autism is very likely hereditary between twins, with an 80 percent chance between identical twins.

It's worth mentioning that many experts believe genetic mutations are not the sole cause of autism. Some environmental factors and maternal immune issues may also contribute. While these causes are not ruled out completely, they most likely only influence or intensify certain autism traits. At the end of the day, it's genetics that most strongly dictates autism development.

Do You Inherit an Autism Gene?

You might be wondering whether there is such a thing as an ASD gene. The simple answer is: no, not necessarily. There is no singular gene that causes autism.

Autism tends to stem from mutations within a number of different genes. However, there are some conditions related to autism that do stem from mutations in one single gene. These include Rett syndrome and Fragile X syndrome.

Research also suggests that females require a greater accumulation of genetic mutations to develop ASD. Males also tend to inherit their autism from unaffected mothers who might carry the relevant DNA and pass it down.

This shows us that females are a little more resistant to genetic mutations and therefore need a much greater genetic load to develop ASD.

Get To Know Your DNA With Sequencing

Is autism hereditary? Your family genetics can play a key role in whether a child develops ASD. When you get the right testing done, you can better prepare for a diagnosis like ASD and other rare diseases. Knowledge is key to understanding what works best for you and your family.

If you're interested in learning more about your DNA and any genetic predispositions you might have, Sequencing is your go-to. We offer clinical-grade, safe, and secure kits to test your DNA in the privacy of your own home. Sequencing's whole genome sequencing reads 100% of your DNA across over 30,000 genes, including an assessment for rare genetic variants associated with autism. It's as simple as a mouth swab and you could learn a great deal of information about your health.

Learn more about whole genome sequencing from Sequencing, or upload your existing DNA data for free to get started today.