Autism Origins: How Do People Get Autism?

Discover how people get autism, the genetic and environmental factors, and the power of early intervention.

reuben kesherim
Ruben Kesherim
April 4, 2024

Autism Origins: How Do People Get Autism?

Understanding Autism Spectrum Disorder

In order to comprehend how individuals develop autism, it's first crucial to understand the basics of Autism Spectrum Disorder (ASD).

Defining Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a developmental disability resulting from differences in the brain. Individuals diagnosed with ASD often exhibit challenges in social communication and interaction, alongside displaying restricted or repetitive behaviors or interests. The spectrum of autism means that individuals with ASD may also present diverse ways of learning, moving, or paying attention. This diversity makes ASD a complex disorder that affects each person differently.

The causes of autism are not fully understood. However, contributing factors are thought to include genetics, differences in brain anatomy, and exposure to certain environmental substances. These factors could potentially lead to the development of ASD in children.

Prevalence of Autism

The prevalence of autism has been on the rise in recent years. Current estimates from the CDC's Autism and Developmental Disabilities Monitoring Network indicate that approximately 1 in 44 children have been identified with Autism Spectrum Disorder (ASD) across communities in the United States. This aligns with the 2021 prevalence estimates from MedlinePlus which also states that 1 in 44 children in the United States is diagnosed with ASD.

Year Prevalence
2021 1 in 44

This increasing prevalence underscores the importance of understanding how autism occurs, in order to develop effective strategies for early detection and intervention. The following sections will delve further into the origins of autism, debunk common misconceptions, and highlight the importance of early intervention.

Origins of Autism

The origins of autism, often questioned as 'how do people get autism', are multifactorial and complex. Research indicates that both genetic and environmental factors play a significant role in the development of this disorder.

Genetic Factors in Autism

Autism is a developmental disability caused by differences in the brain. It is characterized by problems with social communication and interaction, as well as restricted or repetitive behaviors or interests. While the exact cause(s) of autism are unknown, genetic factors and differences in brain anatomy are thought to contribute significantly to the development of autism.

Current research indicates that there isn't a single autism gene responsible for the disorder. Instead, many different genes may increase a person's susceptibility to developing autism. Some of these genes may influence brain development or how brain cells communicate, while others may determine how susceptible a person is to environmental triggers of autism.

Although the link between genetics and autism is complex and not fully understood, it's clear that genetics play a crucial role in the development of the disorder. Further research is needed to better understand the complex interplay between genetics and other factors in the development of autism.

Environmental Factors and Autism

Environmental factors, both pre- and post-natal, also play an integral role in autism pathogenesis. Prenatal risk factors include advanced parental age, metabolic syndrome, maternal infections, and maternal mental health. Natal risk factors include abnormal gestational age, fetal distress, and cesarean delivery. Postnatal risk factors include low birth weight and postnatal infections [4].

Children exposed to higher levels of some air pollutants before and after birth were more likely to have autism. Research has also linked autism to children of mothers who lived near farms that spread pesticides or worked around hazardous chemicals during pregnancy [5]. Researchers have also studied certain chemicals and pollutants that can affect the nervous systems and developing fetuses to understand their potential contribution to autism. These chemicals include flame retardants added to electronics, appliances, mattresses, carpets, as well as phthalates used in plastics, soaps, shampoos, and other products.

Environmental factors contributing to autism are other than DNA and affect a child before, during, or after birth. Genetic variations, environmental factors like air pollutants, and maternal health during pregnancy are studied for their impact on autism. It's important to note that while these environmental factors may increase the risk of developing autism, they do not cause autism on their own. Instead, they may interact with genetic factors to increase a person's susceptibility to the disorder.

Debunking Autism Misconceptions

Understanding how people get autism involves addressing some common misconceptions. Misinformation about autism spectrum disorder (ASD) can lead to unnecessary fear and confusion, especially regarding its causes. Two of the most prevalent misconceptions relate to vaccines and misunderstood causes of autism.

Vaccines and Autism: Dispelling Myths

One of the most persistent myths about ASD is the supposed link between vaccines and autism. This myth stems from concerns about thimerosal, a mercury-containing compound used as a preservative in some vaccines. However, the Centers for Disease Control and Prevention (CDC) highlights that since 2003, there have been nine CDC-funded or conducted studies that found no link between thimerosal-containing vaccines and ASD, and no link between the measles, mumps, and rubella (MMR) vaccine and ASD in children.

Furthermore, even before studies showed that thimerosal was not harmful, it was removed or reduced to trace amounts in all childhood vaccines between 1999 and 2001 as a precaution [3]. Currently, the only type of vaccine that contains thimerosal are flu vaccines packaged in multidose vials, with thimerosal-free alternatives available.

Besides thimerosal, some people have had concerns about other vaccine ingredients in relation to ASD. However, the CDC affirms that no links have been found between any vaccine ingredients and ASD.

Other Misunderstood Causes

Another misconception about autism is the role of certain environmental factors. While research has not found any link between vaccines and autism, environmental factors contributing to autism are other than DNA and can affect a child before, during, or after birth. These include elements like air pollutants and the mother's health during pregnancy.

Studies have shown that up to 10 percent of people contributing DNA to the SPARK autism study have variations in autism genes, with most variations being de novo. Genetic variations in autism genes, particularly de novo variations, play a significant role in autism.

In addition, the timing of conception and parental age have been linked to autism risk. Children conceived less than 18 months after an older sibling or more than five years after an older sibling have a higher likelihood of autism. Parental age, genetic factors, and environmental influences like nutritional factors are considered in understanding autism risk [5].

In conclusion, understanding the misconceptions about autism is crucial in comprehending the actual causes of autism. It's important to rely on scientific evidence and avoid misinformation when trying to understand how people get autism.

Autism and Early Development

Understanding the early development of children diagnosed with Autism Spectrum Disorder (ASD) is crucial to gaining insight into 'how do people get autism'. This section will focus on two key aspects – early social and language skills and the importance of joint attention.

Early Social and Language Skills

Many children on the autism spectrum may show developmental differences during their infant and toddler years, especially in social and language skills. While children with ASD usually reach physical milestones like sitting, crawling, and walking on time, subtler differences in the development of gestures, pretend play, and social language may go unnoticed by families and doctors [6].

Children on the autism spectrum often show delayed or absent social communication skills at every stage of development compared to children without autism spectrum disorder. For instance, they may use words for objects before using words for people or family members, and echo or repeat what they hear for a longer period [6].

Additionally, about 25% of children later diagnosed with autism spectrum disorder may experience regression in language skills and become more socially withdrawn between the ages of 15 and 24 months.

Importance of Joint Attention

One of the most important developmental differences between children on the autism spectrum and children without ASD is a delay in or lack of joint attention. Delays in joint attention skills are found in most children with ASD.

Joint attention refers to the shared focus of two individuals on an object. It is achieved when one individual alerts another to an object by means of eye-gazing, pointing, or other verbal or non-verbal indications. This ability to engage in joint attention behaviors is crucial for the development of language, social interaction, and cognitive skills.

Children with ASD often struggle with joint attention, which can affect their ability to learn from social experiences, understand others' perspectives, and form meaningful social connections. Therefore, recognizing and addressing these early signs of autism can be instrumental in improving the child's developmental trajectory and quality of life.

Identifying Autism in Early Childhood

Early identification of Autism Spectrum Disorder (ASD) can make a significant difference in a child's development, allowing for more effective early interventions. This is why it's crucial to recognize the early signs of autism, especially language regression, withdrawal, and nonverbal communication delays.

Language Regression and Withdrawal

In some children with autism, there may be a regression in language skills and social interactions. This means a child might suddenly stop using words or sentences they previously learned and become more socially withdrawn. According to, about 25% of children later diagnosed with autism spectrum disorder may experience this regression between the ages of 15 and 24 months.

Parents, caregivers, and educators should be aware of these changes, as they can be early indicators of autism. Sudden withdrawal from social interactions or a noticeable decrease in verbal communication could be a sign that a child is on the autism spectrum. Keep an eye out for these signs and consult a healthcare professional if you notice any persistent changes in your child's behavior.

Recognizing Nonverbal Communication Delays

Nonverbal communication is another crucial aspect to consider when identifying autism in early childhood. Nonverbal communication involves gestures, facial expressions, and body language that we use to communicate without words. Children on the autism spectrum often show delays in these skills.

For instance, they may use words for objects before using words for people or family members, and they might echo or repeat what they hear for a longer period than children without autism [6].

Additionally, children with autism usually show delayed or absent social communication skills at every stage of joint attention development, which involves the shared focus of two individuals on an object or event, typically achieved by using gestures and eye contact.

Recognizing these early signs of autism, such as language regression, withdrawal, and nonverbal communication delays, is vital for early intervention and providing the necessary support for children on the autism spectrum. However, remember that each child is unique and these signs can vary from one child to another. Always consult with a healthcare provider for a comprehensive evaluation if you have concerns about your child's development.

The Impact of Early Intervention

The role of early intervention in managing Autism Spectrum Disorder (ASD) is significant. Focused on starting treatment at an early age, it aims to develop a child's full potential and reduce various autistic symptoms and language deficits. This section will discuss the effectiveness of early autism intervention and the crucial ages for treatment.

Effectiveness of Early Autism Intervention

A study conducted by NCBI examined the effectiveness of early intervention in reducing autistic symptoms and language deficits in children with ASD. The study compared children aged 36-47 months with those aged 48-60 months.

The findings revealed that early intervention was more effective in reducing autistic symptoms in younger children. These symptoms include repetitive behaviors, social interaction deficits, and socio-emotional development issues. However, when it came to language abilities, there was no significant difference between the two age groups. This suggests that while early intervention can significantly reduce the symptoms of ASD, its impact on language development, a common challenge in children with ASD, is not as pronounced.

The Crucial Ages for Treatment

The study underscores the importance of recognizing communication deficits in infants and starting therapy early to maximize a child's potential. However, it also emphasizes the need to determine and establish guidelines about the particular ages that are crucial for starting treatment in certain developmental aspects.

While the study did not specify these crucial ages, the findings suggest that the earlier intervention begins, the more effective it could be in managing autistic symptoms. This further highlights the importance of early diagnosis and intervention in children with ASD.

As research continues to unfold, parents and caregivers of children with ASD can take heart in the fact that early intervention can make a significant difference. By focusing on early detection and intervention, we can better support individuals with ASD and help them reach their full potential.