Expanding Our Knowledge About the Science of Autism: Achievements from IDDRCs

April 28, 2016

Scott Pomeroy, MD, PhD
Children's Hospital Intellectual and
Developmental Disabilities Research Center

Harvard Medical School
Boston, MA

As we acknowledge individuals with autism as well as advocates and allies during Autism Awareness and Acceptance Month, it is important to stop and consider the direct contributions of one's own peers. As a neurologist, I find myself particularly driven to reflect upon how significant advances in research lead to a greater understanding of autism that is relevant to individuals with autism, their families, and the broader community. Accordingly, I take pride in the accomplishments of my fellow researchers who conduct their work through the national network of Intellectual and Developmental Disabilities Research Centers (IDDRCs), supported and funded by the Eunice Kennedy Shriver National Institute of Child Health and Development of the National Institutes of Health (NIH). Originally established by the NIH in 1963 as "centers of excellence" for research, the IDDRCs have been among the foremost actors committed to understanding the biological basis of intellectual and developmental disabilities. Along with the University Centers for Excellence in Developmental Disabilities (UCEDDs) and the Leadership Education in Neurodevelopmental and Related Disabilities Programs (LENDs), IDDRCs constitute a vital part of the Association of University Centers on Disabilities (AUCD) network.

All fifteen IDDRCs are filled with brilliant scientists whose work expands our knowledge about the science of autism, which in turn influences more enlightened, effective strategies for education. As I reflect upon the many scientists who have made important contributions to the IDDRCs' body of autism research during the past year, a few readily come to mind. These studies cover different periods throughout human development, collectively offering deep, diverse insights as to when and how autism may originate. These studies encompass the diversity that has been associated with the causality of autism; additionally, they report on cutting edge interventions for autism.

Several of these researchers' findings cast new light upon environmental and biological factors that affect the incidence of autism. A group of IDDRC researchers at the Carolina Institute for Developmental Disabilities (CIDD) in Chapel Hill, NC, recently revealed new evidence of a link between autism and a group of chemical substances that are used in farming. The team found that a certain set of agricultural pesticides and fungicides alter particular brain processes in a manner that is characteristic of individuals with autism, a phenomenon known as transcriptional mimicry. Their work offers noteworthy new evidence that manmade chemicals may be an important environmental factor in the development of autism.

Research into the role of genetic factors in autism also led to a significant breakthrough at the University of Washington Center on Human Development and Disability in Seattle, WA, where investigators discovered loss of function of a gene in individuals with autism. The gene in question, DYRK1A, is associated with neurocognitive deficits also connected to Down syndrome. In addition, the individuals examined in the study displayed physical characteristics that indicate the existence of a previously unknown syndrome. This discovery of a possible new form of autism demonstrates how IDDRC research continues to add to the ever-growing base of scientific knowledge about the genetic underpinnings of autism.

Over the past year, IDDRC researchers have also advanced knowledge of maternal links to autism before the birth of a child. A study performed at the University of California-Davis MIND Institute in Sacramento, CA, found that in animal models maternal autoantibodies can be produced against specific proteins expressed during fetal brain development. This suggests that the autoantibodies (which form part of the mother's immune system) can cross the placenta and target the developing fetal brain, resulting in a subtype of autism. The MIND Institute's work raises the possibility that therapeutic interventions that successfully prevent these autoantibodies' harmful effects could eventually lead to future treatment options for certain subtypes of autism. These discoveries indicate that much still remains to be explored regarding the relative roles the environment and genes may play in autism.

Brain structural differences have long been described in individuals with autism, and many scientists at IDDRCs have pursued work over the past year that provide a window into the relationship between brain structure and function. One such team at the Carolina Institute for Developmental Disabilities conducted a recent study showing over several time points in the first two years of life, children who were diagnosed with autism showed thickening in the corpus callosum. The corpus callosum, a neuron bridge between the left and right sides of the brain, consists of nerve fibers that enable communications between the two hemispheres of the brain. Children whose corpus callosum was especially thick exhibited repetitive behaviors that are sometimes characteristic of individuals with autism. The increased size of the corpus callosum may reflect brain overgrowth that scientists have observed in individuals with autism for many years. This study provides an important window into early neurodevelopment in autism. In the future, as more is known about changes to neurons in those with autism, anatomical differences such as a thickening corpus callosum may be followed closely to determine if interventions could change some behaviors.

Scientists from all of the nation's IDDRCs continue to make groundbreaking contributions to the ways in which we understand autism. Their work not only deepens scientific knowledge of the genetics of autism but also exposes new forms of ASD and helps identify abnormalities in brain structure and function that may explain behaviors found in individuals with autism. The output of IDDRC researchers forms an essential foundation for those with autism and the communities that support them.

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The Association of University Centers on Disabilities (AUCD), located in Silver Spring, MD, promotes and supports a national network of interdisciplinary centers on disabilities. The members of AUCD represent every U.S. state and territory and include 67 University Centers for Excellence in Developmental Disabilities (UCEDD), 43 Interdisciplinary Leadership Education in Neurodevelopmental and Related Disabilities (LEND) Programs and 15 Intellectual and Developmental Disabilities Research Centers (IDDRC). Together, these organizations advance policies and practices that improve the health, education, social, and economic well-being of people with developmental and other disabilities, their families, and their communities, in support of independence, productivity, and healthy and satisfying quality of life.