Cellular and Molecular Neurobiology

, Volume 30, Issue 2, pp 161–171 | Cite as

Understanding and Determining the Etiology of Autism

Review Paper
First Online:
Received:
Accepted:

Abstract

Worldwide, the rate of autism has been steadily rising. There are several environmental factors in concert with genetic susceptibilities that are contributing to this rise. Impaired methylation and mutations of mecp2 have been associated with autistic spectrum disorders, and related Rett syndrome. Genetic polymorphisms of cytochrome P450 enzymes have also been linked to autism, specifically CYP27B1 that is essential for proper vitamin D metabolism. Vitamin D is important for neuronal growth and neurodevelopment, and defects in metabolism or deficiency have been implicated in autistic individuals. Other factors that have been considered include: maternally derived antibodies, maternal infection, heavy metal exposure, folic acid supplementation, epigenetics, measles, mumps, rubella vaccination, and even electromagnetic radiation. In each case, the consequences, whether direct or indirect, negatively affect the nervous system, neurodevelopment, and environmental responsive genes. The etiology of autism is a topic of controversial debate, while researchers strive to achieve a common objective. The goal is to identify the cause(s) of autism to understand the complex interplay between environment and gene regulation. There is optimism that specific causes and risk factors will be identified. The results of future investigations will facilitate enhanced screening, prevention, and therapy for “at risk” and autistic patients.

Keywords

Autism Vitamin D Methylation Folic acid Methyl-CpG-binding protein (mecp2) Methylenetetrahydrofolate reductase (MTHFR) Calcitriol Autoantibodies Glucocorticoids CYP27B1 MMR vaccine Heavy metals 
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Notes

Acknowledgments

The author would like to acknowledge Egidio Currenti, Research Scientist at the New York State Department of Health/Wadsworth Center and David O. Carpenter, MD, Director of the Institute of Health and Environment at the State University of New York at Albany for their encouragement and support.

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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Center for Nanoscale Science and Engineering (CNSE)State University of New York (SUNY)AlbanyUSA

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