Much attention has been paid to purported environmental causes of autism. Controversy has raged over both the MMR vaccine itself and the use of thimerosal, a mercury based preservative used in vaccines as a potential cause of autism.
As prominent a figue as Robert Kennedy Jr has pushed the thimerosal theory before the US Congress and the world. There is however precious little scientific support to date for the vaccine/thimerosal theories. Recent environmental theories include Lyme Disease and television as possible causes of autism.
Notwithstanding the focus on potential environmental causes of autism it is heartening to read that research continues on genetic factors. Genetic research is an important element to the early identification and treatment of autism including development of specific treatments for individual autistic persons as discussed in a very readable article by Dr. John Bernard, president of the Children’s Research Institute, published in the Columbus Dispatch:
"Identical twins have identical genes, while fraternal twins are genetically similar, but not identical. When identical twins have autism, both are affected about 60 percent of the time, whereas fraternal twins are both affected only about 5 percent of the time.
These findings strongly suggest a genetic basis for many cases of autism.
But current thinking is that autism spectrum disorders do not result from genetic factors alone. It is likely that unknown environmental factors also are involved, perhaps as a result of genetic susceptibility.
It is probable that each of the autism spectrum disorders is associated with a specific genetic abnormality. However, scientists involved in the search for specific genetic abnormalities in autism are challenged by the complex variability of individual cases.
Unless individual children can be accurately and specifically classified within the autism spectrum, the search for underlying genes is clouded. Fortunately, specific genetic abnormalities are now being discovered for some of the rare and distinctive types of autism spectrum disorders.
Discovering specific genetic abnormalities associated with autism spectrum disorders might help detect them earlier in life than currently is possible.
Children then could receive customized treatment programs at the earliest possible age, when the prospect for success is best. It is also possible that drug treatments can be designed by researchers to specifically modify the genetic abnormality involved. "
http://www.dispatch.com/science/science.php?story=dispatch/2007/01/16/20070116-D5-04.html
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