Current State of Autism Research

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Current State of Autism Research
James B. Adams, Ph.D. Professor, Arizona State University Science Director, Autism Research Institute/Defeat Autism Now! Parent of a 17-year-old girl with autism
What is Autism?
Autism is a label for people who have major impairments in three areas: speech/communication social interaction/friendships restricted, repetitive, stereotypic behaviors Autism is a spectrum disorder: Autism / PDD-NOS/ Aspergers Impairment in social skills is common to all Likely due to multiple causes.
Research Tools for Diagnosing Autism • Autism Diagnostic Interview – Revised (ADI-Revised): 2-4 hour interview with parents of child’s history • Autism Diagnostic Observation Schedule (ADOS) – 1 hour structured interaction with child Primarily used for research, not by clinicians
Co-occurring symptoms
• Mental Retardation – but must be tested with non-verbal IQ test • Seizures: 25% (and 60% without seizures have subclinical seizures) • Diarrhea/Constipation: 50% • Sleep problems: 50% • Low muscle tone: 30% • Pica: eating non-food items: 30% • Sensory Sensitivies: touch, vision, sound, taste, smell, pain; under- and/or over-sensitive
Early Onset vs. Regression
Data from Autism Research Institute (over 30,000 parental reports)
In US, latest report by CDC cites 1 in 150 for autism spectrum disorders (autism, PDDNOS, Asperger’s). In UK, a new unpublished study by Simon Baron-Cohen at Cambridge University found 1 in 100, and estimates the actual rate at 1 in 60.
Genetic or Environmental Cause?
• Studies of identical twins reveal:
– Co-occurrence is roughly 60% for autism, and roughly 90% for speech delays; if 100%, then only due to genes; so genes are important, but so are unknown environmental factors.
• If a couple has one child with autism, then 510% chance other children will have autism, and 25% chance of major speech delay (so carefully monitor siblings) Genetic vulnerability + environmental exposure
Which Genes?
• Many genetics studies of autism, but they generally disagree, since too few subjects and too many genes • Probably 10-20 genes involved in complex manner • In 2 similar conditions, Fragile X and Rett’s Syndrome, a single gene has been identified for each
Known Genetic Factors
There are several rare genetic disorders that greatly increase the risk of developing autism. These disorders include PKU, creatine formation/transport deficiency (uncommon), adenylosuccinate lyase deficiency, Angelman’s syndrome, Fragile X, Rett’s syndrome, neurofibromatosis, tuberous sclerosis, and others. However, these disorders account for only roughly 5-10% of the cases of autism.
Which Environmental Causes?
• No general agreement • Possible causes with limited scientific data include:
– Impaired methylation – Oxidative stress – Mercury/toxic metals poisoning (due to limited excretion because of low glutathione) – Pesticide exposure (esp. organophosphates and organochlorides) – Excessive oral antibiotic usage – Vaccine damage (especially MMR) – Lack of essential minerals (sulfate, iodine, lithium) – Other unknown factors
Rapid increase in incidence
• • • • 1970’s: 2-3 per 10,000 2008: 1 per 150 (autism spectrum); Now affects about 1 in 94 boys, since 4:1 boy:girl ratio In California (which has best statistics), autism now accounts for 45% of all new developmental disabilities
• Arizona: – 1996: 633 people with moderate/severe autism served by DDD – 1999: 1057 – 2003: 1917 – 2005: 2500 – 2009: 3500
Why rising rate of autism?
• Partly due to better awareness/diagnosis, but that is only modest effect (per study by MIND Institute) • Not due to genetics alone – gene pool normally changes very slowly, although environmental toxicants can cause permanent genetic changes/damage • So, primary reason is increased exposure to environmental factor (toxid metals, pesticides, antibiotics, MMR, iodine deficiency, other?).
New Research on Risk of Autism
Preliminary research by Jill James et al on abnormalities in methylation cycle and glutathione in MOTHERS of children with autism
Oxidative Stress and transmethylation/transsulfuration
Methionine Methylation THF 5,10CH2THF
Cell Methylation
Adenosine Homocystein B6 CBS e B6 3 Cystathionine
1 Folate Cycle 2 Transmethylation 3 Transsulfuration
Cysteine GSH GSSG
Antioxidant Redox Potential (GSH/GSSG)
Intervention Trial with MethylB12 and Folinic Acid
Plasma Metabolite Concentration Autism Pre-treatment (n = 40) 21 ± 4b 66 ± 13b 15.2 ± 5 4.7 ± 1.5b 4.8 ± 1.8 191 ± 24b 5.4 ± 1.3b 1.5 ± 0.4b 0.28 ± 0.08b 21 ± 6b 6 ± 2b
b Signficantly different from
Autism Posttreatment (n = 40) 22 ± 3 69 ± 12 14.8 ± 4 5.0 ± 2.0 5.3 ± 1.1 215 ± 19 6.2 ± 1.2 1.8 ± 0.4 0.22 ± 0.06 30 ± 9 9±3
p valuea
Methionine SAM (nmol/L) SAH (nmol/L) SAM/SAH (µmol/L) Homocysteine (µmol/L) Cysteine (µmol/L) Total Glutathione (µmol/L) Free Glutathione (µmol/L) GSSG (µmol/L) tGSH/GSSG fGSH/GSSG
ns ns ns ns 0.04 0.001 0.001 0.008 0.001 0.001 0.001
Maternal Methionine Cycle Metabolites:
Research by Jill James et al. Autism Moms Moms (n = 46) Methionine (µM/L) SAM (nM/L) SAH (nM/L) SAM/SAH Ratio Homocysteine (µM/L)
*statistically significant
(n= 200)
24 ± 5 80 ± 19
26 ± 6 83 ± 13
33 ± 14* 23 ± 8.4 3.1 ± 1.7* 4.0 ± 1.4 11 ± 3.9*
7.6 ± 1.6
It would be a very good idea to ask your physician to check your “total” homocysteine
Maternal Transsulfuration Metabolites
Autism Moms Cysteine (µM/L) Total GSH (µM/L) Free GSH (µM/L) GSSG (µM/L) Total GSH/GSSG 232 ± 40 5.1 ± 1.7* 1.5 ± 0.5* 0.30 ± 0.08* 17 ± 8 ControlMoms 231 ± 20 7.3 ± 1.5 2.6 ± 0.6 0.24±0.04 31 ± 10*
*statistically significant
Metabolite imbalance and the risk of being a mother of a child with autism
Stratified Group SAH >30µMol/L) SAM/SAH <2.5 tGSH/GSSG <20 SAM/SAH <2.5 and tGSH/GSSG <20 Control Mothers
Case Mothers
Odds Ratio (Risk) 6.9 10.7 15.2 46
14% 10% 11% 3%
54% 54% 65% 41%
In other words, 41% of ASD mothers had a 46x higher chance of having a child with autism, associated with abnormal methylation and oxidative stress
It is not possible to determine from this data whether the abnormal metabolic profile in parents is genetically determined or whether it simply reflects the stress of living with an autistic child Question: Would testing for abnormal methylation/glutathione in mothers and/or newborns, and treating it, reduce the risk of autism? Is this one possible method for preventing autism?
Vulnerable to Toxins
• Decreased glutathione would make fetus more vulnerable to toxins, including toxic metals and pesticides • Consistent with studies linking toxic metals (Windham et al 2006) and pesticide exposure (Roberts et al 2007) to risk of developing autism
New research on possible cause of 12% of cases of autism by Judy van de Water and colleagues at Mind Institute A study of the mothers of children with autism (n=61) found that 12% of them had antibodies to fetal brain tissue. These antibodies were not found in any typical children (n=62). Larger study of 300 children ongoing, and results are similar.
Heavy Chain
Light Chain
Summary of maternal antibodies to fetal brain proteins :
• Researchers found a specific subset of antibodies to fetal brain proteins in the blood of a subset of mothers whose children have autism. • These antibodies occur most frequently in those mothers who have children with regressive autism. • Similar findings have been demonstrated in work by Zimmerman and Singer against both rodent and human fetal brain.
The Autoimmune Phenomenon
Question: Are the antibodies pathogenic? Researchers currently have both primate and murine (mouse) models underway to determine the potential effect of exposure to IgG from the autistic maternal population during gestation on behavioral outcome.
Primate model--Pilot study
• The gestating dams were exposed to 3 IV injections of IgG beginning late 1st trimester with 2 additional injections during the second trimester.
– Group A exposed animals had 4 live births. – Group B exposed animals had 2 live births and will be repeated.
• The offspring were monitored for several developmental criteria including motor coordination, mother preference test, and social interaction.
Mother preference task
• Increased  midline  crossings  • Demonstrated  no preference  for own mother
Social Dyad: Measure of stereotypic
episodes with familiar pairings
• The weaned animals were placed in the observation cage with either a familiar monkey from their social group or an unfamiliar monkey. • The AU treated offspring demonstrated severe stereotypies when placed in this environment.
• It appears that 12% of mothers of children with autism have antibodies to fetal brain tissue. • When injected into pregnant monkeys, those antibodies cause autistic-like behavior in their offspring. • Currently working on commercialization of this test, so that mothers can know if they have this risk factor. • Unknown what causes this abnormal antibody production in mothers.
In autism, there are many abnormalities in many organs and systems, including the immune system, GI tract, brain, nutrition, metabolism, and detoxification. The challenge is to determine which are primary, and which are secondary consequences, so that we know which to treat. One way to do this is by focusing on biomarkers that correlate with the severity of autism. However, it is unlikely that any one biomarker will cover all cases; rather, we expect several biomarkers for different causes and phenotypes of autism.
Biomarkers (cont.)
Biomarkers that correlate with the severity of autism include: Urinary opioid peptides Total IgG (Heuer et al, 2008) R = -0.33, p<0.0001 (ABC) Porphyrins (Geier et al, 2008) R=0.28-0.31, p<0.05 (CARS) Serotonin (Adams et al, unpublished) R= - 0.37 (3 tests) Plasma Sulfate (Adams et al, unpublished) R=-0.42 (3 tests) Lysozyme (Adams et al, unpublished) R=0.47 (ATEC) Gut symptoms (Adams et al, unpublished) R=0.66 (ATEC) In other words, many systems are affected in autism, and each contributes to the severity of autism, on average, with a lot of variation between children. Note: R=0.33 means it explains about 10% of the variation in autism severity (R2 = %)
GI Severity
• Overall GI symptom severity (GISS) correlates highly with autism severity (ATEC), R=0.66 • Lysozymes (a marker of GI inflammation) correlates strongly with autism severity (ATEC), R=0.47 • So, gut inflammation and GI symptoms have an important connection to autism
Reduced Levels of Immunoglobulin in Children with Autism Correlates with Behavioral Symptoms
•Heuer, Luke*1, 7,8, Ashwood, Paul*2, 7,8 ,  Schauer, Joseph 1, 7,8, Goines, Paula 1, 7,8,, ,  Hertz­Picciotto, Irva3,7,8, Hansen, Robin4,7,8,   Croen, Lisa A5,  Pessah, Isaac N6,7,8, Van  de Water, Judy**1,7,8,  •As part of the Children’s Center for  Environmental Health
Reduced levels of IgG and IgM are indicative of an underlying  defect in the immune system of children with autism.
Total IgG
22.5 20.0 17.5 15.0 12.5 10.0 7.5 5.0 2.5 0.0 Autism
* *
Total IgM
* *
1.75 1.50 1.25 1.00 0.75 0.50 0.25 0.00 Autism
Total IgA
2000 1500 1000 500 0
Total IgE
• This study provides a novel association between immune dysfunction and behavioral parameters in autism.
Biomarkers (continued)
To determine which correlations are the most important, it is possible to use Regression Analysis (multiple correlations) ex. Autism Severity = a (peptides) + b (porphyrins) + c (glutathione) We have used regression analysis in two studies, and found that we can explain approximately half the severity of autism in each study.
Regression Analysis – from DMSA study, Adams et al
Compare severity of autism with glutathione and metal tests adjusted R2 Most significant metals • ATEC: 0.22 p=0.003 Pb-9, Sb-b • SAS: 0.36 p=0.002 Pb-b • PDD-BI: 0.25 p= 0.004 Sb-9, W-b, Sn-9 • ADOS: 0.49 p=0.0003 Hg-b, Al-b, Hg-9
All four scales of autism severity can be partially explained in terms of heavy metal excretion, with a very high statistical significance. Suggests 22-49% of autism severity appears to be due to toxic metals, especially lead, antimony, and mercury.
Regression Analysis – from Nutritional Assessment study, Adams et al
Compare severity of autism with nutritional biomarkers • ATEC: • SAS: • PDD-BI: adjusted R2 0.34 p=0.0003 Most significant factors Serotonin, ATP, NADH free carnitine Serotonin, free sulfate Serotonin, free sulfate
0.27 0.20
p=0.001 p<0.002
All three scales of autism severity can be partially explained in terms of these factors, with a very high statistical significance. Suggests part of autism severity related to abnormalities in serotonin, free sulfate, and mitochondrial factors (ATP, NADH, carnitine)
Two major lifetime studies for adults – note that most of these adults had little or no behavioral or medical intervention: Autism: 90% of adults unable to work, unable to live independently, < 1 social interaction/month Asperger’s (50% with college degrees): similar prognosis – social skills limit use of intellectual abilities Grim prognosis if untreated, but many treatments now available, and there is MUCH more hope
Autism is TREATABLE!
Behavioral Therapies Biomedical Therapies Many children now greatly improve, and some even recover, due to behavioral and/or biomedical interventions
Autism Therapies
• Applied Behavior Analysis– most widely accepted/used • Relationship Development Intervention (RDI) – new • Other therapies
Biomedical Treatments for Autism
(based on the Defeat Autism Now! Guidelines)
• • • • • • • • • • • • • • Improve Diet Food Allergies GFCF Diet (no wheat, no dairy) Vitamin/Mineral Supplements High-Dose Vitamin B6 and Magnesium Essential Fatty Acids Amino Acids Gut Treatments Thyroid Supplements Sulfation Glutathione Detoxification Anti-Viral Treatments Immune System Regulation
Future Research Needs
Biomarkers Focus on biomarkers, especially those that correlate with severity of autism (need to integrate medical studies with behavioral assessments) Focus on treatments that relate to biomarkers that correlate with severity of autism. We have many treatment options, but need to rigorously assess the efficacy of each. Determine risk factors for autism, so that we learn how to prevent it.
Future Research (cont.)
Pre-Screening: It is unlikely that a treatment will help all or even most children. So, it is important to use biomarkers to determine who is most likely to benefit. Example: a treatment study with essential fatty acids (EFA) – only enroll children with low levels (we found that those who consumed little or no seafood were much more likely to improve than those who consumed 3+ seafood servings/month
Future Research Needs (cont.)
Multi-Treatments: Almost all studies look at the effect of only 1 treatment, which usually helps only a subset of children, to a limited extent. Since our goal is 100% recovery of the child, we need to investigate treating all of their known problems, instead of only one of them. Example: We are planning a multi-treatment study that will test most of the DAN! guidelines, tailored to the individual based on testing. It will include a personalized special diet, vitamins/minerals, amino acids, essential fatty acids, gut treatments, methyl-B12/folinic acid, thyroid testing, etc. The goal is to assess the effect of the total, integrated set of treatments.
Future Research Needs (continued)
Funding We need to shift public and private funding from unsuccessful, over-funded areas (genetics, brain research) to new areas that directly relate to prevention and treatment ARI appreciates the support of many donors, which have allowed it to fund many studies on the causes of autism and how to treat and prevent it.