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Autism and Environmental Factors

Autism and Environmental Factors

Omar Bagasra, Cherilyn Heggen, Muhammad I. Hossain (Illustrator)

ISBN: 978-1-119-04227-3

Feb 2018, Wiley-Blackwell

320 pages

$120.99

Description

Explores environmental factors during fetal development that may contribute to autism

It is well documented that in the majority of the cases, an autistic child's brain has acquired the genetic and organismal abnormalities that were initiated during the first trimester of their gestational period. Yet, scientists still don’t know what is causing these abnormalities; this book explains how the human brain develops and what the critical stages are in which a fetal brain may acquire genetic and developmental abnormalities. It presents scientific data supporting previous anecdotal observations to attempt to understand the complex puzzle that is autism. From chemical fragrances to herbicides, synthetic chemicals are abundant in everyday life and this book examines the evidence surrounding these chemicals and their effects, including on the developing human brain and how that might explain certain characteristics observed in autism. 

Discussing various aspects of potential ASD causing factors, Autism and Environmental Factors brings together as many pieces of the autism puzzle as possible in one place to begin to clarify the picture and spark discussion to ensure a safe environment for everyone, especially our developing children.

  • Discusses the genetic and environmental factors that may contribute to autism
  • Covers how the human brain develops and the critical stages in which a fetal brain may acquire genetic and developmental abnormalities
  • Describes the rapid proliferation of synthetic chemicals in our modern world and the effects on the developing human brain—endocrine-disturbing chemicals that alter DNA, epigenetics, and hormones
  • Written in a clear and accessible style

Autism and Environmental Factors is an important book for researchers and students in neuroscience, neuroanatomy, developmental neurobiology and anyone focusing on autism research.

Acknowledgments xi

Prologue xiii

1 Introduction to Autism Spectrum Disorders 1

Smell of Autism 5

The Roundup™ Conundrum 7

Testosterone and Male Gender Bias 9

Connecting the Dots 12

Why Is There a “Spectrum” in Autism? 20

Are Genetic Mutations the Cause of Autism? 23

ASD Parent and Affected Child Exome Sequencing Display

De Novo Mutation 23

More Than 1,000 Genetic and Genomic Disorders and Still Counting 24

Why Do Certain Chemicals Induce Specific Depletions of

Certain Brain Compartments? 30

Genesis of an ASD Brain 31

Pinpointing Critical Steps Where the Autistic Brain Emerges 32

Is Finding Mutations the Path to Discovering the Genesis of ASD? 34

Does Brain Size Matter? 36

How Autism Develops in a Fetal Brain 36

Why Is There a “Spectrum” in ASD? 39

ASD and Vaccines 41

Thimerosal Containing Mercury Stays in the Body and Is Very Toxic 42

Summary 43

References 43

2 What is Autism? 51

Legacy of Autism 51

A Short History of Autism 53

DSM]5 and the ASD Spectrum 60

Changes in ASD diagnosis approved by the APA 61

The impact of the Recent DSM]5 Changes on Diagnosis and Support Practices 61

A New ASD Diagnosis Category: Social Communication Disorder 62

ASD or a Giant Spectrum of Socioneuropsychological Disorders 62

Asperger Syndrome 63

Pervasive Developmental Disorder Not Otherwise Specified 63

Autistic Disorder 64

Rett Syndrome 64

Childhood Disintegrative Disorder 64

Is Autism a Genetic Disease? 65

Synthetic Chemicals Lack Coevolutionary Adaptation 66

Myth of the Genetic Origin of Autism 67

Phenotypic Heterogeneity in Autism 67

Why Fragile X Syndrome or Tuberous Sclerosis Should Not Be Included in ASD 70

Tuberous Sclerosis 71

Is Finding Mutation the Path to Discovering the Origin of ASD? 72

How Quickly Does Human DNA Mutate? 73

What is the Mutation Rate in the Whole Human Genome? 74

Does Brain Size Matter? 74

Genetics versus Environment 75

References 77

3 Olfaction and Autism 83

How Do We Smell? 87

Summary and Conclusions 92

References 92

4 Oxytocin, Arginine Vasopressin and Autism Spectrum Disorder 97

Oxytocin 97

Why Oxytocin Therapy May be Important for ASD? 99

Hormones, Neuropeptide Arginine Vasopressin and

Oxytocin in ASD 102

Development of Oxytocin and AVP Neurons in Various

Animals and in Man 103

Oxytocin and Social Experience in Development 104

Oxytocin and Developmental Neurological Disorders 106

Exogenous Oxytocin Treatments in Humans 108

Intranasal and Intravenous Oxytocin Studies in ASD 109

Oxytocin Trials in ASD: Beyond the Hype and Hope 110

Summary and Conclusions 112

References 113

5 Male Gender Bias and Levels of Male Hormones During Fetal

Development 123

Association between 2D:4D Ratio and Brain Connection

Development 129

Male and Female Estrogen and Testosterone Hormone Regulations 130

Are there Synthetic Chemicals that Humans Are Not Evolutionarily Exposed To? 130

Why Male Gender Bias? 131

Male and Female Brains in a Test Tube 132

Effects of Three Different Levels of Testosterone on Neuronal Morphology 133

Molecular Basis of Gender Bias in ASD 134

References 136

6 Maternal Twins and Male Gender Bias in Autism Spectrum Disorders 143

The Conundrum of ASD Discordance in Maternal Twins 146

Role of Environment in Maternal Twins revealed by Numerous Methods under Many Conditions 149

What Types of Discordance are Observed in Maternal Twins? 149

Differences in Frontal and Limbic Brain Activation in Monozygotic Twin Pairs Discordant for Severe Stressful Life Events 150

Structural Connectivity of the Brain of a Child with ASD and That of the Unaffected Identical Twin 150

Differences in Genomic and Epigenomic Expression in Monozygotic Twins Discordant for Rett Syndrome 150

Differences in CNV between Discordant Monozygotic Twins with Congenital Heart Defects 151

History of Autism Becoming a Genetic Disease 151

Many Diseases That Were Considered Genetic are Being Reassessed 152

De Novo Mutations 156

To find a Scientific Analysis of ASD Genesis 158

What are Neuroblastomas? 159

What Method Did We Use? 160

Possible Etiologies of Autism 160

Epigenetic Explained 160

Epigenetic Changes and the Environment: How Lifestyle Can Influence Epigenetic Change from One Generation to the Next 161

Factors Other Than Environment That May Be Contributing to ASD 161

Older Age of Mother and Increased Risk 161

Conclusion and Summary 163

References 163

7 Autism and Exposure to Environmental Chemicals 169

Contribution of Fragrances to ASD 178

Effects of Fragrances on Male Oxytocin]Receptor Positive Neurons 184

Effects of Fragrances on Female Oxytocin]Receptor Positive Neurons 186

How Synthetic Chemicals in Fragrances Affect Fetal Brain Development 186

Synthetic Musks 186

How Do Synthetic Musks Get Into the Food Chain? 189

How Are People Exposed to Synthetic Musks? 189

Musks in Food 191

Diethyl Phthalate 191

Octinoxate 193

Benzyl Benzoate and Benzyl Salicylate 194

d]Limonene 194

α]Pinene 195

Synthetic EDCs 195

Why Is It Important To Look at EDCs and Their Potential Effects on Our Next Generations? 196

Where in Fetal Life Are Androgen Receptors Expressed? 199

Why Testosterone is Essential for Engineering a Male Brain 200

Spatial Memory 207

Anxiety]Related Behavior 207

Play Fighting and Aggression 208

Adverse Effects of EDCs and Their Mechanisms of Action 208

Effects of Testosterone or AR Mimicking EDCs 211

Early Puberty in Males 214

Change in Sex Ratio 215

Effects of EDCs on Neurodevelopmental and Neuroendocrine Systems 215

EDC Effects on Steroid Hormone Receptors in the Brain 217

Are the EDCs and other Synthetic Chemicals Depopulating the Human Race? 219

Summary 223

References 224

8 Maternal Antibodies to Fetal Brain Neurons and Autism 235

Link between Damage to the Fetal Brain and Maternal Antibodies: A Double Jeopardy 235

Are there Examples of Such an Immune Mechanism? 236

Rh Incompatibility 236

ABO Incompatibility 237

Why are Fetal Neuroantigens Immunogenic to the Maternal Immune System? 238

Is There Any Evidence of a Link Between Synthetic Chemicals Exposure, Neurotoxicity, and Autoimmunity? 241

The Relationship between Autoimmunity and ASD 241

The Detection of Fetal Brain Neuroantigens in the Maternal Blood 241

What are the Functions of the Neuroantigens that are Being Destroyed by the Maternal Antibodies? 243

Animal Models and Neuroantibodies to Autism 245

Rhesus Macaques Model 245

Studies Using Rodent Models 246

Why Do Some Autistic Children Have Bigger Brains? 246

Is There a Link between Autoimmunity and Other Forms of Neurodevelopmental or Neurodegenerative Disorders? 248

A Chicken and Egg Conundrum 250

Tourette Syndrome and Obsessive Compulsive Disorder 250

Other Contributing Factors in Neuropsychiatric Disorders 250

Infectious Flu Virus 250

Influenza Vaccine and Narcolepsy 250

Other Viral and Nonviral Infections 252

Blood–Brain Barrier 254

What is the BBB? 254

Summary and Conclusions 256

References 257

9 Vaccines and Autism 261

Childhood Vaccines and Regressive Autism 261

Politics Versus Science in the Vaccination Era 262

A Short Glimpse of the History of Vaccines: Justification for Using Vaccines 264

What is in the Vaccines? 265

Thimerosal 270

What is the Evidence That Organomercurial Vaccines Pose a Higher Risk of Regressive Autism? 272

Why Thimerosal]Containing Vaccines are Harmful: A Scientific Narrative 273

How Much Mercury is Given to Children Before the Age of 3 years? 274

Why Do Only Small Numbers of Children Develop Regressive Autism After Vaccination? 274

Can Measurements of Abnormal Cytokines Identify Children Who Are at Increased Risk for Regressive ASD? 278

Summary of Contributing Immunological Factors to ASD 278

References 279

Epilogue 287

Index 291