Explores environmental factors during fetal development that may contribute to autism
It is well documented that in the majority of 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.
Table of Contents
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
]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
