JERUSALEM, April 25 (UPI) -- Some siblings of children with autism have been diagnosed with delayed verbal, cognitive and motor development, according to Israeli researchers.
The siblings of the autistic children ranged in age from 14 months to four and half years, according to the findings published in a special issue of the Journal of Autism and Developmental Disorders.
Professor Nurit Yirmiya and doctoral candidate Yifat Gamliel of the Hebrew University of Jerusalem and Dr. Marian Sigman of the University of California, Los Angeles, found that after the age of four and a half, most of the children were able to close the gap between their development and that of other children of the same age who had siblings with normal development, except for some small delays in verbal abilities.
The reasons for this phenomenon can be traced to the genetic tendency of children in the former group to carry an endophenotype of autism -- an hereditary characteristic that is normally associated with some condition but is not a direct symptom of that condition, according to Yirmiya.
"Siblings of children with autism are likely to inherit genes that will cause a weakened expression of autistic symptoms," Yirmiya said in a statement.
