Scientists have not yet agreed a definitive cause for the disorder but certain theories are gaining currency. We explore possible genetic causes, brain defects and the disputed statistical link to the MMR vaccination program.
Sarah Spence: The cause of autism at this point is completely unknown. Portia Iverson: We have to remember that for a good 40 or 50 years, the scientific community mistakenly thought that autism was caused by bad parenting and was an emotional disorder, so very little research was done. Sarah Spence: Well in the last five years, there has been an explosion in research in genetics. Portia Iverson: We know genes are involved in autism because of the, in identical twins the occurrence of both twins being autistic is very high. Sarah Spence: And the risk of having a second affected child is 40, 50, maybe even a 100 times the general population risk. Portia Iverson: We have created the world's largest gene bank and we're very proud that, that's one of our biggest accomplishments. We have an over 400 families in this gene bank. Each family has at least two children with autism and these are the kind of very precious families that are needed to study the genetics of autism. Sarah Spence: There have been studies that suggested that the way, that the cells in the brain are organized are very different in children with autism than children without autism. It's starting to give us clues about which areas of the brain involved. So there is a size difference in a nucleus called the Amygdale or there is a size difference in an area of the cerebellum, the little back part of the brain. But if you look at the brain scan of a child with autism, it will look very, very normal. Portia Iverson: A lot has been learned in the last five years in tremendous amount about how to repair brain circuitry, how to get the brain to rewires itself or even establish neurocircuitry where none had previously been established. So we have an initiative on neuroplasticity where we are bringing to bear this kind of knowledge on how can we get the child with autism or even the adult with autism, the tools for neuro retraining. Sarah Spence: The link between MMR vaccine and autism is actually very weak. In terms of scientific evidence, the problem is that the link in people's minds is actually very strong. Portia Iverson: We do get a lot of phone calls at the Cure Autism Now Foundation from parents saying that they believe that their child became autistic shortly after getting a vaccination. Sarah Spence: Now in good science and doing a good epidemiology, people have gone backwards and looked and there are just as many children who had that regression, had that loss of other skills that they'd gained and then stopped. They say they stopped talking or they stopped making eye contact or they stopped socializing or being engaged. Just as often right before, there are MMR vaccines as right after. Portia Iverson: I think it's very important that the government agencies take this public health issues extremely seriously and do the research that's necessary. To show either that vaccine are involved in triggering autism or that they're not because we don't want to disrupt the whole vaccination program if it's not true and at the same time if it is true, we really need to know.