Simple answers elude scientists in search for autism's cause

graphic: Yarek Waszul / NY Times

Is it nature or nuture? Studies indicate that both genetics and environmental factors play a role in causing autism, but clear connections prove elusive and doctors are often at a loss when it comes to offering practical guidance to parents.

An aritcle this week in the New York Times describes the difficulties in teasing apart the various factors contributing to a condition that itself often seems like a moving target. In 'Environment' Poses a Knotty Challenge in Autism, author Perri Klass, M.D. says "Genes matter, but we usually can't tell how. Environmental exposures matter, but we usually don't know which." Recent studies of autism in both fraternal and identical twins only underline the apparent complexities.

Many scientists now believe autism results both from genetic predisposition and from environmental influence, but the term "environment" itself introduces its own complications. According to Irva Hertz-Picciotto, a professor of epidemiology at the University of California, Davis, MIND Institute, environment refers to anything that is not the inherited DNA and include many factors including maternal health and nutrition, stress, exposure to chemicals and perhaps even exposure to a microbe.

How these factors affect the expression of genetic potential is perhaps another question yet again.
Results from a number of studies have associated some specific factors with incidences of autism, however none of the data seems to indicate cause and effect. Yet.

"Every case is probably a result of the confluence of many factors," Dr. Hertz-Picciotto said. "No case probably has one cause."

Which make the condition so concerning to parents - and the continued support of families with treatment and services so important, even in these diffcult economic times.

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If you have questions about the services available to someone you know with special needs, you can visit the Resources page on the Parent Hospital Association website for a list of government agencies that may be able to help. You can also send an email to PHA at info@parenthospitalassociation.org and someone should be able to point you in the right direction.