Families share traits of autistic children
Recent studies have shown that relatives of people with autism also display behaviours and brain differences associated with the condition, even though they themselves do not have it.
An MRI study compared the brains of 40 parents with autistic children to those of 40 age-matched controls — and showed that the parents who had an autistic child shared several differences in brain structure with their offspring.
In another study, brothers of autistic children were found to avoid eye contact with others, a common feature of autism. In addition, the amygdala, a region important for processing emotions, particularly fear, was shrunken in the brothers, just as it is in autistic people.
A further complexity in the underlying biology of autism was reported by Antonio Persico from the University of Rome. He found certain genetic variations linked with autism in North America were not present in autistic families in Italy. It is possible that there are regional differences in the environmental factors that interact with different genes to trigger autism.
It has been known for years that family members of people with autism may share some traits. However, the finding that there are differences in brain structure in parents of children with autism compared to parents of children without autism is new.