The causes of autism are still being looked into. Many experts believe that there isn't one specific 'cause', and that there are genetic factors. We are always looking to understand more about autism, and welcome any research in this area. There is strong evidence to suggest that autism can be caused by a variety of physical factors, all of which affect brain development — it is not due to emotional deprivation or the way a person has been brought up.
Evidence suggests that autism may be genetic. Scientists have been attempting to identify which genes might be implicated in autism for some years. Autism is likely to have multiple genes responsible rather than a single gene. There is no link between autism and vaccines. Much research has been devoted to this issue over the years and the results have comprehensively shown there is no link.
Find out more on the NHS website. There is no known 'cure' for autism. We also believe that autism does not need a 'cure' and should be seen as a difference, not a disadvantage. We also warn people about fake cures and potentially harmful interventions here. This does not mean that autistic people do not face challenges, but with the right support in place, they are more than capable of living fulfilling and happy lives.
Because autism is a 'spectrum' condition it affects different people in different ways. It is therefore very difficult to generalise about how an autistic person will develop over time. Each person is different, and an intervention or coping strategy which works well with one person may not be appropriate or effective with another.
The characteristics of autism can present themselves in a wide variety of combinations. Two people with the same diagnosis can have a very different profile of needs and skills. There is a growing movement among autistic adults who don't think in terms of 'curing' a disorder but instead of celebrating diversity. This is not to suggest that autistic people or those with other diagnoses do not find life challenging, but that they see it as a different way of communicating, thinking, and interacting.
Recently, researchers have discovered other genetic mutations in children diagnosed with autism, including some that have not yet been designated as named syndromes. While each of these disorders is rare, in aggregate, they may account for 20 percent or more of all autism cases.
People with ASD also have a higher than average risk of having epilepsy. Children whose language skills regress early in life — before age 3 — appear to have a risk of developing epilepsy or seizure-like brain activity.
About 20 to 30 percent of children with ASD develop epilepsy by the time they reach adulthood. Additionally, people with both ASD and intellectual disability have the greatest risk of developing seizure disorder.
ASD symptoms can vary greatly from person to person depending on the severity of the disorder. Symptoms may even go unrecognized for young children who have mild ASD or less debilitating handicaps.
Autism spectrum disorder is diagnosed by clinicians based on symptoms, signs, and testing according to the Diagnostic and Statistical Manual of Mental Disorders-V, a guide created by the American Psychiatric Association used to diagnose mental disorders. Children should be screened for developmental delays during periodic checkups and specifically for autism at and month well-child visits. If screening instruments indicate the possibility of ASD, a more comprehensive evaluation is usually indicated.
A comprehensive evaluation requires a multidisciplinary team, including a psychologist, neurologist, psychiatrist, speech therapist, and other professionals who diagnose and treat children with ASD. The team members will conduct a thorough neurological assessment and in-depth cognitive and language testing.
Because hearing problems can cause behaviors that could be mistaken for ASD, children with delayed speech development should also have their hearing tested. Scientists believe that both genetics and environment likely play a role in ASD. There is great concern that rates of autism have been increasing in recent decades without full explanation as to why.
Researchers have identified a number of genes associated with the disorder. Imaging studies of people with ASD have found differences in the development of several regions of the brain. Studies suggest that ASD could be a result of disruptions in normal brain growth very early in development. These disruptions may be the result of defects in genes that control brain development and regulate how brain cells communicate with each other. Autism is more common in children born prematurely.
Environmental factors may also play a role in gene function and development, but no specific environmental causes have yet been identified. The theory that parental practices are responsible for ASD has long been disproved. Multiple studies have shown that vaccination to prevent childhood infectious diseases does not increase the risk of autism in the population.
Twin and family studies strongly suggest that some people have a genetic predisposition to autism. Identical twin studies show that if one twin is affected, then the other will be affected between 36 to 95 percent of the time. There are a number of studies in progress to determine the specific genetic factors associated with the development of ASD.
In families with one child with ASD, the risk of having a second child with the disorder also increases. Many of the genes found to be associated with autism are involved in the function of the chemical connections between brain neurons synapses. Researchers are looking for clues about which genes contribute to increased susceptibility. In some cases, parents and other relatives of a child with ASD show mild impairments in social communication skills or engage in repetitive behaviors.
Evidence also suggests that emotional disorders such as bipolar disorder and schizophrenia occur more frequently than average in the families of people with ASD. The mutation then occurs in each cell as the fertilized egg divides. These mutations may affect single genes or they may be changes called copy number variations, in which stretches of DNA containing multiple genes are deleted or duplicated.
Recent studies have shown that people with ASD tend to have more copy number de novo gene mutations than those without the disorder, suggesting that for some the risk of developing ASD is not the result of mutations in individual genes but rather spontaneous coding mutations across many genes. De novo mutations may explain genetic disorders in which an affected child has the mutation in each cell but the parents do not and there is no family pattern to the disorder.
Researchers do not know the exact cause of autism but are investigating a number of theories, including the links among heredity, genetics and medical problems. In many families, there appears to be a pattern of autism or related disabilities , further supporting the theory that the disorder has a genetic basis. While no one gene has been identified as causing autism, researchers are searching for irregular segments of genetic code that children with autism may have inherited.
Other researchers are investigating the possibility that under certain conditions, a cluster of unstable genes may interfere with brain development, resulting in autism. Still other researchers are investigating problems during pregnancy or delivery as well as environmental factors such as viral infections, metabolic imbalances and exposure to chemicals.
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