2004 Grants Funded (CAN)

Molecular Studies in Autism

Huda Zoghbi, M.D., Baylor College of Medicine (Genius Award)
The funds received through the Cure Autism Now Genius Award will allow us to explore new approaches to identify some of the molecular genetic pathways involved in autism. Our strategy will focus on the following hypothesis: Genes that are key in mediating prominent phenotypes seen in autistic patients are likely to be mutated, at least, in a subset of autism patients. A two-pronged approach will be taken to hone in on the most promising candidate pathways.

Oxidative Stress in Autism

Xue Ming, M.D., Ph.D., UMDNJ-New Jersey Medical School (Pilot Project)
Autism is caused by the interaction of genetic and environmental factors. One of the best understood causes of autism is fetal exposure to thalidomide. Thalidomide causes fetal malformation in rabbits by a mechanism involving oxidative stress. Our hypothesis is that a similar mechanism occurs in human autism cases. Oxidative stress could also be involved in the common form of human autism unrelated to thalidomide. Many common environmental toxins can induce oxidative stress in genetically susceptible hosts. Genetic susceptibility factors for autism could include common polymorphic variants of enzymes that normally protect against oxidative stress.

We will test our hypothesis by determining whether individuals with autism have elevated levels of oxidative stress biomarkers in urine and decreased levels of anti-oxidant enzymes in plasma and erythrocytes. We will also test whether the frequency of common polymorphisms of the antioxidant enzyme glutathione peroxidase 1 is altered in autism trios by the transmission/disequilibrium test. We expect to document that reactive oxygen species and oxidative stress mechanisms play an important role in autism, the findings that could lead to new approaches to prevention and treatment of the disorder.

Studies of Neuropeptide and Protease Patterns of Autistic Children to Elucidate Pathophysiological Mechanisms, Facilitate Diagnostics and Allow New Types of Treatment

Andres Grubb, M.D., Ph.D., Lund University Hospital Sweden (Treatment Award)
The pathophysiology of autism involves abnormal communication between neurons, probably associated with abnormal patterns of neuropeptides in the brain. Abnormal levels of neuropeptides might be revealed by proteomic studies of proteins/peptides below 10 kDa in spinal fluid and/or blood plasma. Detection of abnormal levels of peptides in autism will allow generation of new hypotheses concerning its patho-physiology and might facilitate diagnostics and suggest new treatment possibilities. Since most neuropeptides are generated by proteolysis of larger precursor molecules abnormal levels of neuropeptides might be caused by abnormal proteolytic activity.

We have plasma and spinal fluid samples from 20 autistic and 20 control children and a preliminary SELDI-TOF system for studying proteins/peptides below 10 kDa. We have used this system to investigate 4 autistic and 4 control children and have detected two peptides that display uniquely high concentrations in autism.

We plan to collect samples from more than 40 autistic and control children, elaborate the SELDI-TOF system to allow study of at least 200 proteins/peptides below 10 kDa and use this system to detect peptides of uniquely low or high concentration in autism.

We also plan to structurally characterize those two autism-related peptides already identified, as well as those our further research will identify.

We will also directly analyze arginine-vasopressin, oxytocin, prolactin, neurotensin, substance P, TRH, neuropeptide Y and angiotensin in autistic and control children and study the activity of those proteolytic enzymes that might be involved in the metabolism of the (neuro-)peptides that display abnormal concentrations in autism.

Reading and Writing Program for visual Learners

O. Ivar Lovaas, Ph. D., University of California, Los Angeles (Treatment Award)
Research Partner: Chaka Khan Foundation in support of Tallon's Tower
It has long been suspected that the autistic child's failure to develop language may constitute a significant factor in the etiology of autism. The proposed research intends to test the effectiveness of a newly developed Reading and Writing (R&W) Program with young autistic children who are delayed in the acquisition of vocal language. Teaching these children to read and write will allow them to communicate more effectively with parents and caregivers, leading to a better quality of life as well as treatment outcome. A single-case experimental design, multiple baseline across participants, will be implemented in order to determine the effectiveness of the R&W Program. Treatment begins with 6 months of intensive 1:1 behavioral intervention, 40 hrs/week, where the Vocal Language Program will comprise 30 hrs/week of treatment. At the end of 6 months, children will be divided into two groups: visual and vocal learners, based on ability to imitate vocal behavior. Vocal learners will proceed with the standard vocal language program, while visual learners (i.e., non-vocal children) will be assigned to a baseline condition lasting 1 month, 3 months, or 5 months, during which time they will continue receiving vocal language training. During the 6-month treatment phase, participants will receive 15 hrs/week of training in both the Vocal Language Program and the R&W Program. The proposed study will focus on the R&W Program's effect on rates of language acquisition (including facilitation of vocal language) and participants' affect.

Prevention of Autism Spectrum Disorders by Modulating T Cell Responsiveness

David A. Ostrov, Ph.D., University of Florida-College of Medicine (Treatment Award)
Autism is a behaviorally defined developmental disability manifesting in early childhood and affecting approximately 3 in 500 individuals in the United States. Many autistic subjects exhibit immune imbalances in lymphocyte populations and gastrointestinal immunopathology. There is a strong genetic component to autism spectrum disorders, as concordance is observed in 75% of identical twins. Complex interactions between genetic and environmental factors are thought to contribute to autism susceptibility. Several key autism susceptibility loci have been recently described including the HLA-DRB1 gene in the major histocompatibility complex (MHC) class II region on chromosome 6p21. Although a significant proportion of the inherited predisposition to autism maps to the class II region of the MHC, the mechanisms for how these genes influence the initiation of abnormalities in neurological development are not clear. Evidence exists to suggest that class II MHC DR molecules bind self and/or environmental antigens that may trigger T cells capable of recognizing components of the developing nervous system. This proposal aims to prevent autism by building on two recent significant advances in the field: 1) the discovery of genetic linkage between autism and the MHC, and 2) determining the complete sequence of the MHC. The complete sequence of he MHC reveals the full extent of genes in this region that influence susceptibility to autism spectrum disorders. The objective of the proposed study is to establish a method to prevent autism by modulation the function of MHC encoded proteins using structure-based strategies.

Vagus Nerve Stimulation and the Control of Social and Exploratory Behavioral Deficits in a Rodent Model of Autism

Benjamin R. Walker, Ph. D., Georgetown University (Treatment Award)
In an effort to identify and control the neural substrates mediating the altered social and exploratory behavior see in autism, this proposal aims to evaluate the role of brainstem nuclei in the regulation of behavioral alterations caused by developmental cerebellar injuries. Previously we demonstrated that focal inhibition in the medial nucleus of the solitary tract (mNTS), the primary target of afferent vagal fibers, and the lateral parabrachial nucleus (lPBn), an important pontine relay station for ascending projections from the NTS, attenuated limbic motor seizures evoked from the forebrain. In the present proposal, we test the hypotheses that similar inhibition of these brainstem nuclei, via decreases in glutamate or increases in GABA activation, can amiliorate social and exploratory behavior deficits. To this end, we focally applied the GABA agonist muscimol (256 pmol) or the glutamate antagonist kynurenate (634 pmol) into the NTS in control rats and rats with specific developmental lesions to the climbing fibers of the inferior olive nucleus from postnatal exposure to 3-acetylpyridine (85 mg/kg) or mechanical cerebellar damage while recording their social behavior. Preliminary results demonstrate that alterations in glutamate and GABA neurotransmission within the brainstem and pons is capable of lessening the detrimental effects of cerebellar damage in a rodent model of autism. These results suggest that autistic and seizure behaviors may involve similar neural substrates, and that new treatments for seizures, such as vagal nerve stimulation, which alter these pathways may be effective for treating autism.

Smith-Lemli-Opitz Syndrome (SLOS)_and Children with Autism.

Elaine Tierney, M.D., Kennedy Kreiger Institute (Bridge Award)
The investigators seek to determine the incidence of Smith-Lemli-Opitz Syndrome (SLOS) in a cohort of subjects with autism spectrum disorders (ASD) in multiplex families. SLOS is a disorder of cholesterol metabolism that has been found to be associated with autism [Tierney et al., 2000]. In a study of subjects with SLOS [Tierney et al., 2001], it was found that of 17 subjects administered the ADI-R algorithm questions, 9 (53%) met the Autism Diagnostic Interview- Revised (ADI-R) [Lord et al, 1993; Lord et al., 1994] criteria for autism (the algorithm questions but not the complete ADI-R was administered).

The incidence of SLOS among individuals with ASD is unknown. The knowledge of the percentage of individuals in a cohort of multiplex families who have ASD will help the medical community to know which subjects with ASD should have serum testing for SLOS.

The authors propose to test 29 AGRE serum samples from subjects born into multiplex families with ASD for biochemical evidence of SLOS. If any subjects with ASD are found by serum testing to have SLOS, the AGRE database will contact the families and the investigators will then work with the families (if the families wish to contact the investigators) to ensure that they are referred for appropriate medical care, including dietary cholesterol supplementation.

White Matter/Brain development Initiative

Martha Herbert, M.D., Ph.D., Massachusetts General Hospital (Innovator Award)
This project will pursue a suggestive and provocative finding about the brain in autism, namely that we see enlarged superficial, or radiate, white matter in the brains of autistic individuals. White matter is the part of the brain containing the axons or "wires" that connect neurons in different regions to one another; it is white because of the lipid insulation, called myelin, that surrounds each axon. Dr. Herbert's identification of the radiate zone (right under the cerebral cortex, the gray matter where cortical neurons live) as the part of the white matter contributing most to making many autistic brains unusually large is provocative because it gives suggestive leads for further research on many levels at once: timing (something is manifesting postnatally, as we already knew from the fact that head size gets larger after birth), the nature of tissue changes (related to white matter), mechanism (something that affects regulation of white matter development after birth), and functional impact (possible altered connection among regions, that may impair information processing and lead to abnormal behaviors). This project will therefore develop a collaborative research program, because we need coordinated cooperation across disciplines to explain this brain change in an integrative fashion. The project will also expand upon this research effort to develop comprehensive models of autism. Models that integrate the multiple levels of research about autism are much needed to strengthen and speed up our efforts to understand, diagnose, treat and prevent autism.
Research Partners: The Autism Coalition for Research and Education (ACRE) and Daniel and Carol Tyukody, Jr.

GeneWays Project

Andrey Rzhetsky, Ph.D., Columbia University (Innovator Award)
We wish to conduct a two-pronged analysis of autism (as a biological process or a developmental disturbance), making use of the rich information accumulated in several unrelated fields. We will compile information about molecular interactions in human neurons using our unique text-mining facilities (in the GeneWays system), and we will examine a wide spectrum of disorders with which autism shows non-random association (neurological, autoimmune, epidermal, and many other groups of disorders that have a strong hereditary component). Through this joint analysis, we will compile a computational regulatory model of autism. We also hope to list candidate genes by the probability that they harbor genetic polymorphisms that affect the bearer's susceptibility to developing symptoms of autism.

Accurate GSR measurements for people with autism

Dov Sagi, Ph.D. and Yoram Bonneh, Ph.D. Weizmann Institute of Science, Israel (Bridge Award)
The GSR (Galvanic Skin Response) is a potentially useful measure of the level of arousal in people with autism, especially in relation to external or self generated stimulation. This has been demonstrated in two studies, which found abnormal autonomic response in autistic children. The use of GSR could potentially help with many behavioral and educational issues, such as providing the teacher/parent with a simple feedback method to monitor arousal of the child, or it could be used to alert teacher/parent of changes in arousal that might signal the onset of episodes of aggression, or other serious out of control behaviors, allowing the teacher/parent to intervene pro-actively and possibly avert the episode. One major difficulty in using GSR for autism is the need to attach a wired device to the body, which most autistic children do not like. Moreover, typical self-stimulation could alter the GSR signal by the movement of the hands. Our purpose is to explore the potential use of recently developed GSR devices, which are wireless and claimed to be more accurate. This preliminary exploration could lead to further and more elaborate studies in the future.

Neural and Behavioral Correlates of Visual Integration and Visual Search Processing in Autism. A Probe for Early Assessment.

Giovanni Cioni, M. D., Stella Maris Scientific Institute & University of Pisa, Italy (Treatment Grant)
Autism has been considered for decades to be a developmental disorder based on social and communicative impairment. More recently, the possibility of perceptual and sensorial deficits in autism has been considered to be a contingent cause and possible explanation of this disorder. Both ecological observations and systematic studies of autistic subjects have found general abnormalities of perceptual abilities. In particular, there seems to be an imbalance between the processing of local vs. global visual information (e.g. Jolliffe & Baron-Cohen, 1997; Plaisted, O'Riordan & Baron-Cohen, 1998; Mottron, Belleville & Menard, 1999). The goal of this study is to explore the visual cortical processing in autism using Visual Evoked Potential (VEP) and the perceptual processes using psychophysical techniques and eye movement recording. Our aim is to understand how local signals are integrated across space to generate global percepts and visually guided behavior in autism. The identification of the neural substrate underlying these perceptual computations is crucial, because it may represent the neural substrates for feature grouping and figure-ground segregation and because developmental deficits in a common processing architecture may have wider effects on cognitive development. The results of this study may provide fundamental basic knowledge to re-interpret some theories of autism. In fact, it may add knowledge on the early perceptual stages of the cognitive system, providing essential constraints to any middle- and high-level cognitive theory of autism. Moreover, the electrophysiological techniques we will develop may provide a new set of tools for early diagnosis of autism in infancy and early childhood.

Early Identification of Infants and Toddlers at Risk for Autistic Spectrum Disorder (ASD)

Carole Samango-Sprouse,Ed.D, Neurodevelopmental Diagnostic Center for Young Children, Inc. (Bridge Grant)
The proposal study will investigate a quick, efficient and reasonable method to identify infants at risk for ASD. It will increase the health care providers vigilance of a serious disorder and could lead to earlier identification and treatment for ASD.

Otoacoustic Emission Testing of Children with Autism Spectrum Disorders