Zinc and copper metabolism in baby teeth may help predict ASD risk

Mount Sinai Research Could Result in Future Diagnostic System for Autism Spectrum Disorder

Using evidence found in baby teeth, researchers from the Department of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai report that cycles involved in zinc and copper metabolism are dysregulated in autism spectrum disorder (ASD), and can be used to predict who will later develop the disease. The researchers used the teeth to reconstruct prenatal and early-life exposures to nutrient and toxic elements in healthy and autistic children.

Results of the study will be published online in Scientific Advances, a journal published by the American Association for the Advancement of Science, at 2PM EST on May 30th.

This is the first study to generate a 90 percent accurate fetal and early childhood biomarker of ASD using a longitudinal analysis of distinct metabolic pathways. The results of this research could produce a new diagnostic approach for ASD.

About 1 in 68 children has been identified with ASD, according to the U.S. Centers for Disease Control and Prevention. To determine the effects of the dysregulation of zinc and copper metabolism on developing ASD, Mount Sinai researchers used biomarkers in baby teeth collected from twins living in Sweden and replicated these findings in three other populations: a group of non-twin siblings in New York, and two populations of non-related participants from Texas and the United Kingdom.

During fetal and childhood development, a new tooth layer is formed every day. As each of these 'growth rings' forms, an imprint of many of the chemicals circulating in the body is captured in each layer, which provides a chronological record of exposure. The research team used lasers to sample these layers and reconstruct the past exposures along incremental markings, similar to using growth rings on a tree to determine the tree's growth history.

"We found significant divergences between ASD-affected children and their healthy siblings, and used these biomarkers to predict the emergence of disease," said one of the study's first authors, Paul Curtin, PhD, Assistant Professor in the Department of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai. "These findings suggest that the cyclical metabolism of nutrients and toxicants is critical to healthy neurodevelopment, and the emergence of autism."

The other first authors of the study are all from the Department of Environmental Medicine and Public Health at the Icahn School of Medicine: Christine Austin, PhD, Instructor; Austen Curtin, PhD, Data Analyst,; Chris Gennings, PhD, Director of the Division of Biostatistics and Research Professor, and Manish Arora, PhD, BDS, MPH, Professor and Vice Chairman of the Department.

"The results of this study are important because they identify specific pathways related to autism pathology, and could lead to an early warning system for ASD and other neurodevelopmental disorders," said Dr. Arora. "If ASD is diagnosed at a younger age, parents can take advantage of the early introduction of therapies."

In future studies, the research team plans to use baby teeth to study the association of metal metabolic cycles with attention deficit-hyperactivity disorder and other disorders.