What Causes Autism?
Poor parenting does not cause autism, although its symptoms can be confused with abuse or neglect. Autism is a biological condition that can be triggered by a number of factors, most of which are not yet understood. One cause is rubella, which can affect the fetus if the mother is exposed during pregnancy. There are also chromosomal abnormalities including Fragile X and conditions that affect newborns, like infantile spasm, herpes simplex encephalitis and other rare conditions, are also associated with autism. Some people believe that immunizations may cause autism but recent research does not support this theory.The genetics of autism is now being intensively researched. There is general agreement that there is unlikely to be one single gene that causes autism. Instead it is likely to be an interplay of a number of genes. If a family has one child with autism, the risk of recurrence with other children ranges from 3-8 percent.
There is no known single cause for autism, but it is generally accepted by the medical community that it is caused by abnormalities in brain structure or function. Brain scans show differences in the shape and structure of the brain in autistic versus non-autistic children. Researchers are investigating a number of theories, including the link between heredity, genetics and medical problems. While no one gene has been identified as causing autism, in many families there appears to be a pattern of autism or related disabilities, further supporting a genetic basis to the disorder. Researchers are searching for irregular segments of genetic code that autistic children may have inherited. It also appears that some children are born with a higher susceptibility to autism, but researchers have not yet identified a single “trigger” that causes autism to develop. Researchers are also investigating the possibility that, under certain conditions, a cluster of unstable genes may interfere with br
The cause of autism may turn out to be a combination of genetic and environmental factors. Currently, no specific genes or environmental factors have been identified. There continues to be a lot of speculation in the public about things that could cause autism, such as pollutants, viruses, and vaccines. Research findings, however, remain unconvincing and controversial. Knowledge of the causes of developmental disabilities may help prevent future occurrences, but there are thousands of children and adults who need education and therapy today. We know that individuals with these disabilities can learn, grow, and lead high-quality lives. How can we support them? First, each persons needs should be assessed to determine goals. Then, best practices (those with evidence showing their effectiveness) should be used. These include teaching in small steps, providing rewards, and guiding correct performance. Second, related medical conditions should be monitored and the potential positive role of
It is suspected that there may be multiple causes for ASD due to a complex interaction of genetic and environmental factors. Family studies have shed the most light on the genetic contribution to autism. Studies of twins have shown that in identical twins there is about a 75% rate of both twins having autism, while in non-identical twins this occurs about 3% of the time. The inheritance pattern is complex and suggests that a number of genes are involved. For the majority of people with ASD, the cause is not known; however, ASD tend to occur more frequently than expected among individuals who have certain other medical conditions, including Fragile X syndrome, tuberous sclerosis, congenital rubella syndrome, and untreated phenylketonuria (PKU). Some harmful substances ingested during pregnancy also have been associated with an increased risk of autism, specifically, the prescription drug thalidomide.
Related Questions
- If the Lancet case report did not say MMR causes autism, and if his collection of biopsies for research purposes was pre-approved by the Ethical Practices Committee, why is there a case against Dr. Wakefield (and colleagues)?
- What Causes Fragile-X Syndrome, and How Is It Linked to Autism?
- What is known about the causes of autism?
