Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that affects communication, social interaction, and behavior. The exact causes of autism are not fully understood, but research suggests that a combination of genetic and environmental factors, as well as brain development and parental age, may play a role.
Causes and Risk Factors of Autism
4 Main Causes of Autism:
Genetic Factors
Studies have shown that there is a strong genetic component to ASD. It is estimated that up to 90% of the risk for developing autism is due to genetic factors. There are many genes that may contribute to the development of ASD, and research in this area is ongoing.
Chromosomal abnormalities have been identified in some individuals with ASD, affecting brain development. For example, a mutation in the SHANK3 gene has been associated with an increased risk of ASD. Inherited genetic variations may be one of the causes of autism. In some cases, ASD may be inherited from one or both parents who carry a genetic variation that increases the risk of the disorder. Mutations in the CNTNAP2 gene have been linked to an increased risk of ASD.
Environmental Factors
Environmental factors may also be one of the causes of autism. Prenatal exposure to toxins, such as mercury or lead, during pregnancy may increase the risk of ASD. Maternal infection during pregnancy has also been linked to an increased risk of ASD. For example, the rubella virus has been associated with an increased risk of ASD.
Brain Development
Research has shown that there are differences in the brains of individuals with ASD, including differences in the size and structure of certain brain regions. These differences may be considered as one of the causes of autism. Abnormalities in early brain development, such as disruptions in the formation of neural connections during prenatal or early postnatal development, may lead to ASD.
Abnormalities in brain function, such as increased activity in certain brain regions, have also been suggested to contribute to the development of ASD. For example, some individuals with ASD may have increased activity in the amygdala, a brain region that is involved in emotional processing.
Parental Age
There is some evidence to suggest that advanced parental age may be one of the causes of autism. This may be due to changes in the DNA of the sperm or egg as individuals age. One study found that the risk of ASD was higher for fathers over the age of 40 compared to fathers under the age of 30.
Another study found that children born to fathers over the age of 50 were 2.2 times more likely to be diagnosed with ASD than children born to fathers under the age of 25. Similarly, advanced maternal age may also be a risk factor. One study found that the risk of ASD was higher for children born to mothers over the age of 35 compared to mothers under the age of 25.
Conclusion
In conclusion, while the exact causes of autism are not fully understood, research suggests that a combination of genetic and environmental factors, as well as brain development and parental age, may play a role. Further research is needed to fully understand the complex nature of autism spectrum disorder. Early identification and intervention can greatly improve the long-term outcomes for individuals with ASD, and ongoing research is crucial to better understand this complex condition.
Also read: Is autism genetic?
About Olga Sirbu
My name is Olga Sirbu, I am a Board Certified Behavior Analyst (BCBA) and Licensed Applied Behavioral Analyst. My goal is to support and empower families and individuals on the autism spectrum.
Autism Advance is dedicated to training parents and caregivers, providing practical tips, and teaching individuals how to educate kids with autism.
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