Autism Awareness Day: Do Genes Cause Autism? Without a Doubt!


Robert Miller
National Fragile X Foundation
Member of the FXCRC Steering Committee


On this World Autism Awareness Day it is important to remember that one of the significant causes of autism is already known. Fragile X syndrome (FXS) is known by researchers to cause somewhere between 2 percent and 6 percent of all autism diagnoses. So does this mean that all autism has a genetic basis? It is too early to know, but it is no coincidence that researchers who study autism are very interested in FXS, and vice versa. It also explains why FXS experts are often experts on autism. Another indication of the linkage between autism and FXS is the fact that a number of pharmaceutical companies developing new drug treatments are focused on both conditions.

Organizations such as the National Fragile X Foundation have been helping families for many years whose children are diagnosed with autism and for which FXS is the known cause.

Of course, FXS is a medical condition with a known cause, diagnosed through a DNA blood test. The test results confirming the condition have helped many families understand why their child has been diagnosed with autism or as having an autism spectrum disorder. And because FXS is an inherited condition that runs in families, it has also shined a light on other members within the immediate and extended family who may have FXS or, as carriers of the genetic mutation for the condition, may be affected by or at risk for developing one of the Fragile X-associated Disorders that share a common root with FXS. The other conditions—Fragile X-associated tremor/ataxia syndrome (FXTAS) and Fragile X-associated primary ovarian insufficiency (FXPOI)—often manifest in adulthood.

As the world rightfully focuses on autism and struggles to understand its increasing prevalence, the National Fragile X Foundation encourages parents and professionals alike to remember that FXS is one key to understanding the condition. For more information, log onto www.fragilex.org.