"Uncovering environmental causes of autism
CHARGE (Childhood Autism Risks from Genetics and the Environment) was launched in 2003 as a study of 1,000 to 2,000 children with differing patterns of development. The goal is to better understand the causes and contributing factors for autism or developmental delay. Three groups of children are being enrolled in the CHARGE study: children with autism, children with developmental delay who do not have autism and children from the general population. All of them are evaluated for a broad array of exposures and susceptibilities.
Refining our understanding of environment-gene interactions
Little is known about what causes autism or developmental delay. We will learn how genes and the environment interact to change children’s behaviors and skills. By studying a large number of children, we will discover which particular genes and/or environmental exposures might result in non-typical patterns of development and special subtypes of autism or developmental delay."
2010 could be known as the year that serious autism research arising from the genetic-environmental interaction model CHARGE'd to the fore with two major genetic-environmental focused autism research studies being published and receiving widespread attention. 2010 could also come to be known as the year that the "it's gotta be genetic" model of autism causation began its retreat from the battlefield in our attempt to understand autism causes and seek autism cures. Nothing can be done to retroactively counter the time, financial resources, attention and energies lost promoting the ill conceived notion that all autism disorders are 100% genetically based but there are now clear signs we are moving forward in our efforts to understand what causes autism disorders and real progress is being made.
Researchers involved with the recent mitochondrial dysfunction study and the proximity to proximity to highways (and air borne pollutants) study used data from the CHARGE program. In each case the study authors are careful to report the limitations of their studies and to indicate that their studies indicate associations but do not, as yet, identify specific causes of autism disorders. The studies are exploratory and provide the foundation for further research. Such studies are long overdue and are very welcome.
A solid foundation for serious autism research has been established. The autism research paradigm shift whispered about over the last 3 years is now fully emerging and we are seriously studying the interaction of genetic and environmental research. The gene environment model of autism is strongest in California where researchers like Dr. Irva Hertz-Picciotto, principal investigator on the CHARGE study, Dr. Heather E. Volk and Dr. Cecelia Giulvi use data from the CHARGE program as the basis for their research.
The gene environment model of autism was also featured prominently at the US Senate Committee on Environment and Public Works, Subcommittee on Children’s Health hearing entitled, "State of Research on Potential Environmental Health Factors with Autism and Related Neurodevelopment Disorders" in August 2010. One of those who made written submission to the hearing was Dr. Isaac N. Pessah, Director UC Davis Center for Children’s Environmental Health and Disease Prevention Professor of Toxicology and a Co-Investigator with the CHARGE study.
There are signs Canada has also begun to embrace the gene environment model of autism causation. The York Alliance Autism Research Group includes Dr. Dorothy Crawford, focusing on gene environment interaction as causes of autism disorders in her research. Even the US IACC (Interagency Autism Coordinating Committee) has acknowledged, albeit somewhat timidly, the emergence of the gene environment model in understanding autism causation:
"As with many complex disorders, causation is generally thought to involve some forms of genetic risk interacting with some forms of non-genetic environmental exposure. ... In addition, a number of other environmental factors are being explored through research because they are known or suspected to influence early development of the brain and nervous system. Recent studies suggest factors such as parental age, exposure to infections, toxins, and other biological agents may confer environmental risk. ... Progress in identifying environmental factors which increase autism risk has been made recently (Eskenazi et al., 2007; Palmer et al., 2006; Palmer, Blanchard,; Wood, 2009; Rauh et al., 2006; Roberts et al., 2007; Windham et al., 2006), although this area of research has received less scientific attention and far fewer research dollars than genetic risk factors"
I have bold highlighted the last quoted statement from the IACC because it confirms exactly what has been said about autism research funding by autism researches from Dr. Teresa Binstock to Dr. Irva Hertz-Picciotto. Funding dollars have gone overwhelmingly toward genetic based autism research at the expense of environment autism research and that imbalance must be corrected. Hopefully, as the gene environment model continues to gain ground amongst scientists involved in autism research that imbalance will also be corrected by funding authorities from government agencies to Autism Speaks.
It is time to CHARGE ahead with the gene environment interaction model of understanding and researching autism disorders.