Autism: It May Be A Genetic Defect

The autistic child lives in a bizarre world known only to him. He may rock aimlessly back and forth, flap his hands in front of his face or twirl on his toes like a dervish. He may hear some sounds, but ignore others. He may learn to talk, then abruptly stop speaking altogether. For decades specialists regarded autism, which affects at least 300,000 children in the United States, as a severe psychological disorder. Now most authorities consider it to be a physical problem, perhaps caused by neurological defects. And last week a California psychiatrist presented statistics suggesting that the brain damage may be inherited or congenital.

Dr. Edward R. Ritvo of the University of California, Los Angeles, studied autistic children from 230 families. In the test group, he told a meeting of the National Society for Autistic Children in Boston, Ritvo found 25 pairs ofidentical twins; in all cases both of the twins were autistic. Among eighteen sets of nonidentical twins, two pairs were both autistic and five sets included one autistic twin and one who showed "developmental delay," such as a birth defect, delayed speech or walking, impaired vision or hearing or epileptic seizures. Thirty-seven of the families had two autistic children and six had three with the disorder. Seventeen autistic children in the study had relatives outside the immediate family who were autistic.

Such statistics show that some cases of autism are probably inherited through flawed genes, Ritvo says. In other cases, he suspects, something may have occurred in the womb to make the child peculiarly susceptible to environmental influences that trigger autistic behavior. To confirm these speculations, Ritvo and his colleagues plan to check obstetrical records for evidence of birth trauma or histories of infections in the mother, such as German measles. They also plan to conduct blood tests to analyze the children's chromosomes for genetic "markers" of autism, and to see if they have had viral infections affecting the nervous system or immunological deficiencies. Ritvo hopes that ultimately normal people with family histories of autism can be helped by genetic tests, such as amniocentesis, to avoid the disorder in their own children.