Thank you to our friends at Autism Science Digest magazine for allowing us to excerpt this article.
Aluminum Toxicity in Mitochondrial Dysfunction and ASD
By Nancy Mullan, MD, and Amy Yasko, PhD, AMD, FAAIM
Currently, there is intense interest and discussion surrounding the high incidence of mitochondrial disease and/or dysfunction in children with autism spectrum disorders (ASDs). This interest is fueled at least in part by the 2008 Hannah Poling decision.1,2 In this landmark case, the federal government’s Vaccine Injury Compensation Program (VICP) agreed to award damages to the Poling family when their daughter Hannah, who had an underlying mitochondrial disorder, developed autism-like symptoms after receiving a series of vaccines in a single day. Because Hannah Poling’s father is a medical doctor who was in the department of neurology at Johns Hopkins Hospital at the time that his daughter’s vaccine injury occurred, her case carried great weight. The Poling case, therefore, served to draw a great deal more attention to mitochondrial disorders within autism than these disorders had previously received.
A carefully executed review and meta-analysis of mitochondrial dysfunction in ASD by Rossignol and Frye discerned that the prevalence of full syndrome mitochondrial disease in children with ASD is significantly higher than it is in children in general.3 Their analysis also revealed that many children with ASD have findings on laboratory tests that indicate some degree of mitochondrial dysfunction, although not full syndrome mitochondrial disease. Together, these findings indicate a high degree of abnormal mitochondrial function in children with ASD, which other research has corroborated.2,4-9
The cause of the high comorbidity between ASD and mitochondrial dysfunction remains obscure. Most ASD patients do not have a genetic abnormality that would explain the association.4 Nonetheless, there is a great deal of overlap between the symptoms of ASD and the symptoms of genetic mitochondrial diseases, many of which progressively affect multiple body systems. Genetic mitochondrial diseases especially impact organs that have high energy demands, such as the brain and nerves. Because the brain has the highest energy demand of any tissue, mitochondrial disease causes a variety of neurological problems, including intellectual disability, seizures, developmental regression, gastrointestinal problems, and lack of coordination. In addition, because muscles have a high demand for mitochondrial energy, low muscle tone, weakness, and fatigue are features of many mitochondrial diseases. These neurological and muscle-related symptoms are very commonly found in children with ASD as well, though patients who have ASD and biochemical evidence of mitochondrial dysfunction have relatively milder, non-progressive forms of mitochondrial dysfunction when compared with cases of mitochondrial disease caused by genetic aberrations.10
Searching for explanations
The search continues to identify the reason(s) why so many children with ASD have associated abnormal mitochondrial functioning and biomarkers (as shown by results of laboratory testing). Attention is turning away from genetics toward the environment. As a first line of evidence that environmental factors are involved, there is no question that increased free radicals impair mitochondrial function.11 This fact may be particularly significant for children with ASD since . . . read more at Aluminum Toxicity in Mitochondrial Dysfunction and ASD.