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William H Ahearn, Ph.D., BCBA  
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Specialties: Behavior Analysis, Learning Deficits, Autism

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More on autism and vaccines

Mar 06, 2008 - 4 comments

The news media are being fed a new line of misinformation from antivaccinationists and this is being fueled by one case that was recently decided in favor of the plaintiffs in vaccine court.  The government clearly does not think there is a link between autism and vaccines.  In fact, one prominent case has already been dismissed because of the overwhelming evidence against this hypothesis (more on that below).   The following is a summary of the case decided in favor of the parents and the vaccine court decision from a science blog called neurologica, written by a prominent neurologist from Yale, Steven Novella (the entire article can be found at this link: http://www.theness.com/neurologicablog/index.php?p=203 ).  He considers all possibilities and concludes as to which are likely.  Please pass on this information to anyone interested in the topic.

  To summarize the case history, the child in the case appeared normal and healthy, except for chronic otitis media, until about 20 months of age at which time he had a series of vaccines according to the routine vaccination schedule. Two days later the child had a fever to 102.3, was lethargic, irritable, and would arch his back when he cried. The child then developed a rash. It was later determined that the child had: “encephalopathy progressed to persistent loss of previously acquired language, eye contact, and relatedness.” The child regressed and developed symptoms similar to those of autism spectrum disorder. However, the child does not have autism - he has a regressive neurological disorder that includes blood and muscle abnormalities not seen in autism, and any clinical resemblance to autism is not a reflection of a common cause.

Six years after symptoms began the child also developed partial temporal lobe epilepsy that required treatment.

During this time the child also had an extensive workup, which discovered:

A CSF organic acids test, on January 8, 2002, displayed an increased lactate to pyruvate ratio of 28,1 which can be seen in disorders of mitochondrial oxidative phosphorylation.

A muscle biopsy test for oxidative phosphorylation disease revealed abnormal results for Type One and Three.

In February 2004, a mitochondrial DNA (”mtDNA”) point mutation analysis revealed a single nucleotide change in the 16S ribosomal RNA gene (T2387C)

It if often difficult or impossible to draw firm conclusions from a single case, so I will lay out what I see as all the possible alternative hypotheses to explain this information.

1) One possibility is that the child was perfectly normal prior to the vaccines, which caused an encephalitis (inflammation of the brain) which caused brain damage, including the later seizures. The metabolic disorder and mutation may be a red herring and have no bearing on the child’s clinical condition.

2) The mitochondrial disorder predisposed the child to have a reaction from the vaccines, resulting in encephalitis. The subsequent neurological regression was due to some combination of the vaccine-induced encephalitis and the underlying mitochondrial disorder.

3) The child’s mitochondrial mutation is the primary cause of their neurological regression, but that this regression was exacerbated by the vaccine-induced encephalitis (this seems to be the US government’s conclusion).

4) The child has a mitochondrial encephalopathy which is the sole cause of all of the child’s neurological signs and symptoms. The reaction to the vaccines may have played no role at all in the subsequent regression, and the child’s current neurological condition is exactly what it would have been had they never been vaccinated. It is even possible that the encephalitis was merely the first manifestation of the mitochondrial disorder and the timing after the vaccines was merely coincidental.

That lays out the spectrum of possibilities in this case. At this point in time we do not have (or at least I am not privy to) sufficient scientific information to say definitively where along this spectrum the truth lies. The US government’s decision was based partly on this uncertainty - erring on the side of compensating the child and family.

But we can discuss the plausibility of each scenario. Kirby dismisses anything resembling option 4, but his dismissal is naive and unjustified. In fact the patient’s clinical syndrome resembles what is called a mitochondrial encephalopathy - with increased lactic acid, abnormal muscle biopsy, neurological regression, appropriate age of onset, even seizures. It is probably not a coincidence that the child has a point mutation in a gene that has been previously linked to these very mitochondrial disorders. Kirby incorrectly argues:

While it’s true that some inherited forms of Mt disease can manifest as developmental delays, (and even ASD in the form of Rhett Syndrome) these forms are linked to identified genetic mutations, of which T2387C is not involved. In fact little, if anything, is known about the function of this particular gene.

This is misleading. Kirby refers to “this particular gene” which makes me think that he believes T2387C is a gene. It’s not - it describes a point mutation (at location 2387 a thymidine has replaced a cytosine). The gene is the 16S ribosomal RNA gene. Mutations in this gene have been identified to cause mitochondrial encephalopathy. So Kirby is just wrong. It is true that I could not find that this specific mutation has been identified before, but that is common in genetics - a disease is linked to point mutations in a specific gene (or perhaps specific regions of a gene) but most or all families identified have their own specific mutation.

This makes option 4 very plausible - it would be an incredible coincidence if this child just happened to have a mutation in a gene that was known to cause their exact constellation of neurological signs and symptoms and yet the mutation was not the sole or primary cause of those symptoms.

But it does not rule out option 3 - that the mitochondrial disorder was the primary cause of the child’s neurological disorder but that a reaction to the vaccines worsened the ultimate symptoms. Therefore the government’s decision was reasonable - but is absolutely not a concession about any claim made by the petitioners concerning a link between vaccines an autism.

It does, however, make any hypothesis resembling option 1 or 2 extremely unlikely. Further testing regarding the physiological effects of this child’s specific mutation would be helpful, and such testing may be under way but I could find nothing published to date. It is theoretically possible that the identified mutation does not cause a change in the gene product or mitochondrial function, and is therefore just a coincidence. But this is unlikely given the clinical features in this case are a good match to known mutations of that gene.

Kirby, however, apparently wants to wring as much fear and confusion out of these events as he possibly can. So now he speculates wildly that maybe children diagnosed with autism really have this mitochondrial disorder combined with vaccines (he has to keep vaccines in the loop). Given the rarity of such mutations, and the fact that there were specific features in this case that would likely be uncovered in the routine evaluation of a child with autism (like an elevated lactic acid), it is highly unlikely that there are many children with vaccine-triggered mitochondrial encephalopathy mimicking autism out there.

It has been found that some children with autism have mitochondrial dysfunction - one study found that 7.2% of subjects with autism had “definite mitochondrial respiratory chain disorder.” Poling et al, in response to this child’s case, did a retrospective study of children with autism and with other neurological disorders and found that “Aspartate aminotransferase was elevated in 38% of patients with autism compared with 15% of controls.” Such findings are preliminary - the only conclusions that can be drawn is that the association between autism and metabolic disorders requires further investigation. However, these studies did not look at the incidence of suspicious mitochondial mutations in autism, and these findings may not be relevant to this case.

Kirby also wildly speculates that perhaps the evil toxins in vaccines caused the mutation in the first place. He writes:

Use of the AIDS drug AZT, for example, can cause Mt disorders by deleting large segments of mitochondrial DNA. If that is the case, might other exposures to drugs or toxins (i.e., thimerosal, mercury in fish, air pollution, pesticides, live viruses) also cause sporadic Mt disease in certain subsets of children, through similar genotoxic mechanisms?

Among stiff competition, this is perhaps the most absurd and scientifically ignorant thing Kirby has every written. AZT does NOT cause a genetic disorder. AZT blocks DNA replication (it blocks the copying of DNA) - that is its mechanism as an anti-retroviral drug. In patients it can also block mitochondrial DNA replication, thereby causing mitochondrial depletion. This results in there being too few mitochondria (the energy factories of cells) in some cell populations and causes dysfunction in tissue that is especially susceptible to the effects of this dearth of mitochondria. This is a side effect of AZT and also other retrovirals because of sustained use at doses designed to inhibit DNA replication. This does result in some effects that are similar to mitochondrial genetic disorders - because both result in insufficient mitochondrial activity. But that is the only similarity. AZT does not cause a disseminated somatic mutation, which is the incredible analogy that Kirby is making.

What Kirby is suggesting is that in infants and toddlers toxins can cause the same point mutation in millions of different cells throughout the body. Toxin-induced mutations do not cause genetic diseases, unless they occur in a germ cell in which case a mother or father can pass the mutation onto their children. If it occurs in the womb then large cell populations may be affected (whatever cells derive from the cell that had the mutation). But in a child a point mutation would affect only one cell and any cells that derive from it. A toxic mutagen would cause different random point mutations in different cells. This could not cause the mitrochondrial encephalopathy in this child. It can increase the risk of cancer, because cancer can develop from a single mutation in a single cell that causes it to become neoplastic.

Conclusion

This is a unique and idiosyncratic case that raises more questions than it answers. In my opinion as a neurologist, with the information provided, the child has a mitochondrial encephalopathy. The role of the vaccines is unclear, but at worst a rare vaccine reaction exacerbated the underlying mitochondrial disorder. This case has no clear implication for the larger question concerning vaccines and autism, which is likely why both sides agreed to settle.

Yet those who insist, despite the evidence, on claiming that vaccines or mercury are linked to autism are likely to add this permanently to their litany of misinformation and fear-mongering.



Basically, the antivaccination people are pushing this as a victory and it really is not.  As mentioned above, there has already been one case that clearly tested the autism-vaccine hypothesis that was dismissed.  You can read about that here (http://neurodiversity.com/weblog/article/145/)



Blackwell Case Dismissed · Feb 20, 03:45 PM
On February 8, 2008, Judge Stuart R. Berger of the Circuit Court for Baltimore City, Maryland, granted vaccine manufacturer Wyeth’s motion for summary judgment in Blackwell v. Sigma Aldrich, Inc. et al (No. 24-C-04-004829) — a lawsuit in which the plaintiffs alleged that their child’s exposure to thimerosal-containing vaccines caused him to become autistic.

Judge Berger ruled that:

“Upon consideration of Defendant Wyeth’s Motion for Summary Judgment, and the Plaintiffs’ Response filed thereto… [t]his court finds that there is no genuine dispute as to any material fact… Defendant Wyeth is entitled to judgment as a matter of law.”

This ruling comes eight weeks after the court precluded the testimony of plaintiffs’ expert witnesses Dr. Mark Geier. Dr. Stephen Siebert, Dr. Elizabeth A. Mumper, Prof. Richard C. Deth, and Prof. Boyd E. Haley:

“In sum, the plaintiffs, the proponents of the above-identified expert witnesses, have failed in their burden of proving that the bases of the expert witnesses’ testimony are generally accepted as reliable within the relevant scientific field… [T]hey have failed to show that the methodologies underlying their expert witness’ opinions are generally accepted to be reliable in the relevant scientific community.”

“[I]t is generally accepted in the relevant scientific community that autism is genetic in origin except in rare instances of prenatal exposures to certain substances at defined periods during pregnancy… [I]t is generally accepted in the relevant scientific community that thimerosal in vaccines does not cause or contribute to neurodevelopmental disorders such as autism.”



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by passionlessDrone, Mar 07, 2008
Hi William H Ahearn -

I found your posting quite interesting.  I'm not convinced on either way re: vaccines and autism, but I do more or less buy into the biomedical approach for treating autism.  In any case, you seem to raise a good point concerning the fact that the T2387C isn't a gene, but rather a specific mutation, and in other cases mutations to this gene are responsible for mitochondrial issues.  This seems to be lost in a lot of the chatter out there on this.  

What I'm struggling to put my head around is a reliable mechanism for determining if this particular mutation can be assumed to have the same effect as other, identified mutations on the same gene.  It would seem this is an issue not just for T2387C, but for any other previously undocumented SNP mutations.  A few months ago, for example, some set of researchers announced a 'universal' model for autism involving SNPs; others also seemingly more knowledgable than myself point out that everyone on the planet has thousands or millions of SNPs; and clearly just having bunches of single point mutations isn't enough to cause problems for the vast majority of us.  

Clearly, large scale genomic studies wherein specific mutations are found to be risk factors have identified situations wherein specific SNPs raise risk.  However, other than such population based studies looking for this particular mutation, can you give a jerk autism parent trying to figure stuff out an explanation of how well we can assign causation to a newly discovered SNP?  Another way of saying what is bothering me is that it seems likely there could be plenty of other SNP mutations on the specific gene that wouldnd't result in mitochondrial disorders.  

I appreciate the clarity of your writing style.

Thank you and take care!

- pD

(if this double posts, please remove one.  / sorry)

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by William H Ahearn, Ph.D., BCBABlank, Mar 07, 2008
pD

First let me say that I've never met a "jerk autism parent."  Almost all of the parents I meet, even those who do not agree with my opinions, are deeply concerned about their children and want to do what is best for them.  I greatly respect that as a clinician and a parent.  My primary goal is to help these parents and their children and it is work that I really enjoy.  That sometimes leads me to discuss controversial topics such as this one.  I do not believe that a biomedical approach is going to generally help persons with autism unless they have physiological ailments that can be treated through biomedical intervention.  As to the question relating to assigning causation to an SNP, please note that I'm not an expert in genetics and I rely on the expertise of others with this topic.  What I understand is that it is unlikely that a single genetic cause will be found for autism.  Studies that have recently come to light have identified etiologies that appear to be somewhat distinct.  I'm pasting in some of those references below. I also suggest trying to navigate Steven Novella's writings (referenced in original post) for some more insight and a link to a New Scientist article (posted yesterday or the day before) that discusses this issue.

MET protein gene variant
Campbell et al. (2006)
Also found in parents and prev. linked to cancer

100 gene seq. mutations  up to 10% of ASDs?
(Sebat, Wigler et al. 2007; AGRE)

25 gene seq. errors  1% of ASD?
Boston Autism Consortium (2008; CH)

Genes assoc. w/ affiliative behavior (PRL, PRLR, OXTR) variants  % ASD?
Yale Child Center group (2008; incl. Volkmar)

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by jennyr, Mar 27, 2008
Childhood autism and vitamin D deficieny

This topic really has my atttention as I have a small child and am pregnant. In our small circle of friends, 3 children in separate families have been diagnosed. What is causing a reported tenfold increase in childhood autism in the last 20 years? Is it related to new immunization schedules, new artificial sweeteners, or what? I couldn't find any convincing reports. Then I googled 'vitamin D deficiency birth defects'. Harvard and preeminent neurological journals. Definately worth a read.

http://www.medicalnewstoday.com/articles/27692.php
If maternal vitamin D deficiency causes fetal brain damage, more brain-damaged children will be born in the summer.  Brains of summer-born children are making neuronal connections at the fastest rate during the winter and early spring when their mother's vitamin D levels are lowest.  If vitamin D deficiency damaged human brains, then summer-born children should be retained more often, do worse in school, and display more learning disabilities.

At latitude 42 degrees, Boston, Massachusetts has a marked seasonal variation in vitamin D levels.  Dr. Nathlie Badian of Harvard found that boys born in July and August were seven times more likely to have learning disabilities than those born in the cooler months.

http://www.vitamindcouncil.org/
Autism
Research has shown that low maternal vitamin D3 has important ramifications for the developing brain. Vitamin D is a steroid hormone with many important functions in the brain, mediated through the nuclear vitamin D receptor (VDR). Disfunctional VDR demonstrate altered emotional behavior and specific motor deficits.

http://www.vitamindcouncil.org/health/autism/
for an extensive look at the relationship between maternal vit D deficiency and autism

http://www.fightingfatigue.org/?p=1220
The Vitamin D Council states that Vitamin D deficiency can also cause stroke, osteoporosis, muscle weakness, muscle wasting and birth defects.

According to the Vitamin D Council, you will need approximately 4,000 units of Vitamin D per day. You would have to drink 40 glasses of milk a day or take 10 multivitamins a day to get the required amount of Vitamin D. Naturally neither one of these methods is recommended so what are we to do? People typically make about 20,000 units of Vitamin D after 20 minutes of sun exposure, which is about 100 times more than the daily amount of Vitamin D the FDA says we need.


The marked increase in autism rates correlates with a marked cultural decrease in sun exposure.(national recommendations to get your SPF 40 and keep your little kids out of the sun altogether.) Maybe a few minutes of sun a day is good idea.

My prayers, hopes and best wishes are with the parents, the kiddos, the doctors and the scientists.


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by soworried88, Aug 06, 2013
Can u help me plz I've had.a yeast infection and my bf got it frm me and now he has these bumps on his penis and they itch him and are really puffy and both of us have bumps every where now and are itching like crazy we can't even sleep

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