"Can Aspergers be inherited? Our son was recently diagnosed, and now I am wondering if my husband has it too ...their behaviors are very similar."
Aspergers (high functioning autism) is a neurobiological disorder in which known areas of the brain are affected in ways scientists do not yet understand. Aspergers is considered to be inherited in a complex fashion—more complicated than disorders like color-blindness or Huntington’s disease. The recurrence rate for the disorder in siblings of affected children is approximately 2% to 8%, much higher than the rate in the general population, but much lower than in single-gene diseases.
Researchers are getting closer to finding a genetic basis behind autism spectrum disorders. Rett’s syndrome is an autistic disorder for which the exact genetic cause is believed to have been found. In Aspergers, studies suggest problems in several chromosomal (genetic) regions, including areas on the chromosomes 2q, 7q and 15q. While the 7q region is considered the most promising area of study, research studies involving this chromosome in Aspergers have failed to observe its linkage to this region.
For reasons doctors do not know, there are far more boys "diagnosed" than girls (although there may be as many girls with Aspergers as boys, males get diagnosed with the disorder more often). Scientists have evaluated whether or not Aspergers represents an X-linked genetic disorder—one passed down generally from a mother to a son. Unfortunately, there have been cases of father to son transmission of the condition, which means that the disease cannot be X-linked.
In at least one case, two parents with Aspergers had a child that also had Aspergers, but did not have a severe case of the disorder, nor did the child have autism. In another case, identical twins both had Aspergers, but this is not always the case.
While some scientists support the idea that at least a portion of Aspergers isn’t genetic at all, there have been no specific findings associating the syndrome with any environmental condition, including a lack of association of the disease with pregnancy characteristics and pregnancy complications.