nts. Infants are normally interested in social, as opposed to nonsocial environments.
             The cause for autism remains unclear, although most neurological studies seem to indicate a dysfunction in the brain as a possible reason. Autism has been found in children with brain abnormalities such as congenital rubella syndrome, neurofibromatosis, and tuberous sclerosis. Autism can also be present in genetic syndromes such as fragile X syndrome and phenylketonuria. Some research has shown that there may be an autism gene, or two genes working together. These genes are thought to be on the seventh and thirteenth chromosome. The disorder is, in some instances, may be hereditary as shown by twin studies that cite there is a "substantially higher rate in identical twins-so much so that heritablity is over 90%", says Joseph Piven (cited in Applied Genetics News p.1). In a Harvard Mental Health letter (1997) statistics found that the rate of autism and mild retardation in brothers, sisters and fraternal twins of autistics is 50-100 times higher than average and in id!
             entical twins the rate is 65% to 90%. In 1980 it was found that among 11 families with a father diagnosed with autism more than half of their children were autistic. The apparently normal parents of autistic children had undiagnosed mild
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