Statement by Dr. Geri Dawson
Chief Science Officer, Autism Speaks
Chief Science Officer, Autism Speaks
We commend the Poling family for their courage and conviction in fighting to have their case heard and resolved. Their daily struggles reflect the tremendous challenges and frustrations faced by all families affected by autism and other disabilities. Autism Speaks has funded several studies looking at mitochondrial disorders and their possible role in autism. Scientists have been exploring how toxins can affect mitochondrial and neuronal function in autism, as well as how immune challenges, such as vaccines, might affect a child with an underlying vulnerability. This line of research is still in an early stage, so we don't yet have definitive answers. Today's news addresses a single case and shines a bright spotlight on the important need for continued research on these conditions so that we can arrive at clear answers.
Key questions:
Could a vaccine cause a child with Mitochondrial Dysfunction or Disorder to develop autism?
Vaccines stimulate the immune system, which may put stress on the cell function of a child who has asymptomatic mitochondrial dysfunction or disorder such that the child now shows increased symptoms. In an extreme case, the symptoms could involve regression and symptoms of autism.
How is this case important?
We need to fund studies that can help us better understand mitochondrial dysfunction in children with autism and how children with this disorder respond to immune challenges, such as vaccines and infection. We also need to continue to explore how toxins might affect mitochondrial function. There are many questions to be answered: How many children with autism have MD? Can we develop better ways to test for it? What are the best treatments? How can we better identify subgroups of children who may react poorly to vaccines?
What is your advice for parents?
If parents are concerned that their child might have MD, they should talk to their doctor about this to see if testing is appropriate.
Are vaccines safe?
For the vast majority of children, yes. However, we need to conduct research to better understand and identify subgroups of children who may respond poorly to vaccines. Research is needed to better understand mitochondrial dysfunction and how it might interact with vaccines and its role in autism.
What is mitochondrial dysfunction?
Mitochondria are the energy producers of our cells. Therefore, if you have a mitochondrial disorder, you lose function of the mitochondria, which leads to problems with energy production in your cells. It can occur in the brain, in the liver, in the heart, in the muscle, in the peripheral nerves etc. - there are many known mitochondrial disorders that will affect any of these organs because our mitochondria are different in different tissues. Mitochondrial dysfunction is when the mitochondria are still functioning, but just not optimally.
What percentage of children with autism suffer from this?
There have been very few cases of mitochondrial disorders reported in autism. However, since individuals with mitochondrial dysfunction may not show symptoms, it is difficult to determine how prevalent it really is. In one small population-based study in Portugal, approximately 5% of individuals with autism had evidence of some mitochondrial disease.
How does mitochondrial dysfunction affect a child?
Some disorders affect single organs, some affect multiple organs. This can result in difficulties with eye movements, motor problems, cardiomyopathy, hearing and vision problems, seizures, and migraines. It's quite variable and symptoms can appear at any age.
What are the signs that a child has it?
It may present as low muscle tone and recurrent deteriorations. But in many (if not most) cases it is probably asymptomatic.
How do you test for mitochondrial dysfunction?
Doctors typically conduct a blood test to measure AST/ALT and alanine/lysine ratios, for example, or test for urine markers of mitochondrial dysfunction, or conduct a muscle biopsy to assay for specific mitochondrial disorders or mutations in mitochondrial DNA. But there are actually relatively few specific markers and a diagnosis requires clinical judgment.
Is mitochondrial dysfunction treatable?
Yes, although so far treatment is mostly supportive, with supplementation depending on where the dysfunction lies. For instance, complex 1 and complex 2 mitochondrial dysfunctions can be treated with vitamin B2. In other words, you can try to treat with the necessary substrates that will bypass the specific dysfunction or break in the energetics pathway.
How would a vaccine influence a child with MD to cause autism?
An immune stimulation (including any infection) may increase the oxidative stress in cells (which could cause a child with a so far undiagnosed, asymptomatic mitochondrial dysfunction to now show evidence of the dysfunction). But it is also important to remember, an infection is a much greater immune stimulus than a vaccine inoculation.
What percentage of the general population has MD?
We don't know because we don't really know how a minor disruption in mitochondrial function would present and it's difficult to detect, even with repeated testing. In some (most) cases it may even be asymptomatic. Therefore we cannot estimate its prevalence.
Source: Poling, Frye, Shoffner and Zimmerman. “Developmental Regression and Mitochondrial Dysfunction in a Child With Autism”; Journal of Child Neurology / Volume 21, Number 2, February 2006;21:170–172; DOI 10.2310/7010.2006.00032).
Key questions:
Could a vaccine cause a child with Mitochondrial Dysfunction or Disorder to develop autism?
Vaccines stimulate the immune system, which may put stress on the cell function of a child who has asymptomatic mitochondrial dysfunction or disorder such that the child now shows increased symptoms. In an extreme case, the symptoms could involve regression and symptoms of autism.
How is this case important?
We need to fund studies that can help us better understand mitochondrial dysfunction in children with autism and how children with this disorder respond to immune challenges, such as vaccines and infection. We also need to continue to explore how toxins might affect mitochondrial function. There are many questions to be answered: How many children with autism have MD? Can we develop better ways to test for it? What are the best treatments? How can we better identify subgroups of children who may react poorly to vaccines?
What is your advice for parents?
If parents are concerned that their child might have MD, they should talk to their doctor about this to see if testing is appropriate.
Are vaccines safe?
For the vast majority of children, yes. However, we need to conduct research to better understand and identify subgroups of children who may respond poorly to vaccines. Research is needed to better understand mitochondrial dysfunction and how it might interact with vaccines and its role in autism.
What is mitochondrial dysfunction?
Mitochondria are the energy producers of our cells. Therefore, if you have a mitochondrial disorder, you lose function of the mitochondria, which leads to problems with energy production in your cells. It can occur in the brain, in the liver, in the heart, in the muscle, in the peripheral nerves etc. - there are many known mitochondrial disorders that will affect any of these organs because our mitochondria are different in different tissues. Mitochondrial dysfunction is when the mitochondria are still functioning, but just not optimally.
What percentage of children with autism suffer from this?
There have been very few cases of mitochondrial disorders reported in autism. However, since individuals with mitochondrial dysfunction may not show symptoms, it is difficult to determine how prevalent it really is. In one small population-based study in Portugal, approximately 5% of individuals with autism had evidence of some mitochondrial disease.
How does mitochondrial dysfunction affect a child?
Some disorders affect single organs, some affect multiple organs. This can result in difficulties with eye movements, motor problems, cardiomyopathy, hearing and vision problems, seizures, and migraines. It's quite variable and symptoms can appear at any age.
What are the signs that a child has it?
It may present as low muscle tone and recurrent deteriorations. But in many (if not most) cases it is probably asymptomatic.
How do you test for mitochondrial dysfunction?
Doctors typically conduct a blood test to measure AST/ALT and alanine/lysine ratios, for example, or test for urine markers of mitochondrial dysfunction, or conduct a muscle biopsy to assay for specific mitochondrial disorders or mutations in mitochondrial DNA. But there are actually relatively few specific markers and a diagnosis requires clinical judgment.
Is mitochondrial dysfunction treatable?
Yes, although so far treatment is mostly supportive, with supplementation depending on where the dysfunction lies. For instance, complex 1 and complex 2 mitochondrial dysfunctions can be treated with vitamin B2. In other words, you can try to treat with the necessary substrates that will bypass the specific dysfunction or break in the energetics pathway.
How would a vaccine influence a child with MD to cause autism?
An immune stimulation (including any infection) may increase the oxidative stress in cells (which could cause a child with a so far undiagnosed, asymptomatic mitochondrial dysfunction to now show evidence of the dysfunction). But it is also important to remember, an infection is a much greater immune stimulus than a vaccine inoculation.
What percentage of the general population has MD?
We don't know because we don't really know how a minor disruption in mitochondrial function would present and it's difficult to detect, even with repeated testing. In some (most) cases it may even be asymptomatic. Therefore we cannot estimate its prevalence.
Source: Poling, Frye, Shoffner and Zimmerman. “Developmental Regression and Mitochondrial Dysfunction in a Child With Autism”; Journal of Child Neurology / Volume 21, Number 2, February 2006;21:170–172; DOI 10.2310/7010.2006.00032).
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