Causes of Autism

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Causes of Autism

• Autism Spectrum Disorders
• (ASDs)

2
Proposed Causes of Autism Spectrum Disorders

• Low glutathione and oxidative stress
• Vaccines-heavy metal toxicity
• Chromosomes and the mutation or deletion
• of certain genes

3
Low glutathione

• Glutathione is one of the bodies most important
  antioxidants
• Detoxification and release of environmental
  toxins in the liver

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Low Glutathione

• Glutathione is crucial to the protection of the
  cell from toxins
• 80 of children with ASD have reduced levels of
  glutathione

5
Oxidative stress

• Reduced levels of glutathione cause oxidative
  stress
• Occurs when antioxidants are not able to rid the
  body of chemicals
• Can damage cells in the brain, gastrointestinal
  tract, and immune system

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Oxidative stress

• An organism experiences oxidative stress when the
  effects of prooxidants exceed the ability of
  antioxidant systems to neutralize them.

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Oxidative stress
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Vaccines-Heavy Metal Toxicity

• 2008-29 vaccines recommended by the CDC
• Most highly debated cause

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Heavy Metal Toxicity

• Majority of vaccines contained mercury
• 187 times the Environmental Protection Agencys
  daily exposure limit

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Heavy Metal Toxicity

• In 1999 mercury was removed from most vaccines
• Rate of Autism dropped 35 according to an
  article in the Journal of American Physicians and
  Surgeons

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Yeast

• Can worsen behaviors in individual with ASD
  especially those with late onset.
• Exposure to repeated antibiotics kills benign
  microbes that keep yeast under control.

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Yeast

• Result is an overgrowth of yeast that releases
  toxins into the body
• Behavior problems linked to yeast are
• confusion lethargy
  
• Hyperactivity
  irritability
• short attention span aggression

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Chromosomes and Their Genes

• International Molecular Genetic Study of Autism
  Consortium
• Chromosomes being pursued further are
• 2, 7, 15, 16, and X

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Genes

• There is a combination of genes that produce
  symptoms of Autism.
• Approximately 5 or more genes combined need to
  have a duplications, mutations or deletions.

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Chromosome 2

• Neurexin 1
• Codes for proteins involved with communication
  between neurons
• Has been linked to Fragile X

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Chromosome 2

• SLC25A12
• Associated with routines and rituals
• Expressed more strongly in those with ASD
• Higher levels of this gene produced a stronger
  need for routines and rituals

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Chromosome 7

• EN2
• Encodes a protein involved in the cerebellum
• Deficits in social behavior caused by deletion.

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Chromosome 15

• GABRB3
• Works with GABRA5 and GABRG3 genes to make GABA
  receptors that carry messages between nerve
  cells.
• Is associated with those individuals that develop
  epilepsy

19
Chromosome 16

• GRIN2A
• Associated with learning and memory
• Disruption produces other behavioral problems
• Linked to ADHD

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Chromosome X

• MECP2
• Mutations are linked to Rett syndrome
• expression is significantly reduced in a high
  frequency of autism and autism spectrum disorder
  brain samples

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Conclusion

• These are just a few causes that are being
  pursued.
• Parents, doctors, and researchers will continue
  to investigate all the information
• This quest for knowledge will help to provide
  better understanding and more thorough answers.