Gene flaw may link autism, vaccine additive

A study released today by an environmental organization offers support to the theory that a vaccine preservative called thimerosal may contribute to the cause of autism.

The study has found a genetic flaw that sheds further light on how autistic children are metabolically different from healthy children. This may explain why autistic children may not be able to excrete mercury and other heavy metals.

Because of this finding, some doctors also believe that a relatively simple mixture of nutritional supplements may provide a dramatic treatment for autistic children.

The new 18-month autism investigation was conducted by Dr. Jill James, a former Food and Drug Administration research scientist who now works at the University of Arkansas for Medical Sciences.

Her report claims that autistic children have a severe deficiency in glutathione, which James said is the body's most important detoxifier.

The Environmental Working Group, a not-for-profit organization that investigates toxicity in the environment, is using James' study as a way to petition for further thimerosal research.

Many parents and several researchers have speculated that thimerosal, which is 50 percent mercury by weight, is the culprit behind the exponential increase in autism cases over the last decade. Ten years ago, the American Academy of Pediatrics estimated an autism rate of one in 2,500 in the United States. Today, the rate is estimated as high as one in 166. As many as one in six children have neurological disorders. Many believe the rise in autism and the corresponding increase in the nation's vaccine schedule are not coincidental.

Pharmaceutical companies removed thimerosal from required vaccines in 2002, but it still exists in most of the recommended influenza shots.

Autism theorists have for several years hypothesized that certain children are susceptible to heavy-metal toxicity, which poisons the brain.

The reports shows that autistic children have 133 percent more "inactive" glutathione in their bodies than healthy children and 68 percent less "active" glutathione.

The report also gives parents hope. Preliminary results have shown that certain supplements -- folinic acid and methyl B12 -- can bring glutathione back to normal levels.

Dr. Elizabeth Mumper, the CEO for Advocates for Children and associate professor of clinical pediatrics at the University of Virginia Medical School, said she has seen dramatic improvements in some autistic children who have been taking the supplements.

"I don't mean to imply that we can cure autism," she said. "But in this subset, some have moved out of the [autism] spectrum and gone to kindergarten without aid."

She said the metabolic makeup of autistic adults will have to be studied, but she sees no reason why the nutritional aids won't help autistic adults as well.

'Closer and closer'

News of such a breakthrough is exciting for Dena Petzoldt of Fruitland, whose son, Ben, is autistic. Tests have shown that Ben has high levels of heavy metals, including mercury, in his blood. The family has traveled to many states to try various remedies.

"We're just getting closer and closer," she said. "There have to be answers out there because there are so many autistic kids out there. I'll definitely check into this."

James studied the metabolism of 20 autistic children. In a conference call with reporters, she explained she started with 10 plasma samples from autistic children.

The results were "very, very striking," she said. They were so consistently abnormal that she added 10 more samples to her study, just to make sure they were accurate. They came back the same.

Autism is generally regarded as a genetic and environmental mixed bag. James said the genetic causes are complex. There could be 10 genes that contribute to autism.

The new finding makes sense for a number of reasons, she said.

Glutathione levels are naturally lower in males, which could help explain why 70 percent of autistic children are boys. Estrogen, found more predominantly in females, is an antioxidant like glutathione, so girls have more chemical weapons to fight against metal toxins.

The glutathione discovery may also explain why so many autistic children have intestinal disorders.

Glutathione, according to the study, is vital to proper functioning of the intestines.

The Environmental Working Group is waving James' study in the face of the Institute of Medicine.

In May, the IOM -- an independent scientific group commissioned by the Centers for Disease Control and Prevention to delve into the thimerosal issue -- released a report which said there is no evidence suggesting a link between the preservative and autism. It based its findings on five epidemiology studies, including one from Denmark, which has a different vaccine schedule and thus different thimerosal exposure than the United States.

Epidemiology is a mathematical approach to science based on complicated statistics derived from medical databases.

The IOM heard but did not accept the biological evidence, which was only theoretical, the committee said. The IOM also suggested that "further research to find the cause of autism should be directed toward other lines of inquiry."

Dr. David Weldon, a congressman from Florida, has been the leading government anti-thimerosal spokesman.

"The work of Dr. James and other have continued with private support," Weldon said in a statement. "Unfortunately, the National Institutes of Health has not yet dedicated funding to better understand and develop interventions for the epidemic of children suffering from neurological development disorders, particularly those that have resulted from mercury exposures from childhood vaccines.

"Today's study, along with several other recently published scientific studies, demonstrate clearly that the IOM overstated their conclusions."

'Didn't dismiss anything'

Dr. Steve Goodman of Johns Hopkins University School of Medicine in Baltimore sat on the IOM committee that reviewed the evidence.

He told the Southeast Missourian he couldn't speak for the IOM because the committee no longer exists, but he said there was a general feeling that thimerosal would be unlikely to turn out to be the cause of autism. However, he said some of the IOM's statements were misconstrued at the time.

"First of all, we didn't dismiss anything," he said. "We simply stated the epidemiology evidence favored no relationship, which is true. At this point there is no increased risk to the general population.

"What we did say is if you've got a fixed pot, don't spend huge amounts more on epidemiology. What we said was that resources would be better spent on understanding the biology."

For several years a certain segment of the scientific community has suspected that autistic children have a genetic susceptibility to mercury and that thimerosal could be the environmental trigger to autism. So why base a national report on five studies that don't address the theory?

"That's what we're saying," Goodman said.

He said unless the genetic flaws can be identified and a test group can be formed with the same flaws, there is no use for more epidemiology, which suggests no danger to the healthy population.

The anti-thimerosal groups have been making that same argument since May when the IOM report was released.

The IOM did admit in its report that "the committee cannot rule out, based on the epidemiological evidence, the possibility that vaccines contribute to autism in some small subset or very unusual circumstance."

Regardless, major television networks only reported the news of no link, followed by quotes from board members saying funding should be spent elsewhere. Many physicians at the time considered the thimerosal issue a closed book. And, according to a U.S. congressional source speaking on the condition of anonymity, perhaps the National Institutes of Health did too.

The National Institutes of Health has cited the IOM report when it has denied funding for biological research, the source said.

Shortly after the IOM report came out, Columbia University researcher Dr. Mady Hornig published a study showing that mice with genetically susceptible immune systems displayed autistic-like behaviors when given thimerosal.

While the Environmental Working Group acknowledges that James' research doesn't prove a link, the organization says the findings should force the government to pick up the issue again. The epidemiology studies the IOM based its report on assumed that the children had equal toxin-fighting capabilities, the EWG says.

Goodman didn't want to comment specifically on the new study until he reads it.

"This type of study could fit in a much bigger picture and enhance the understanding of autism and the immune system," he said. "It's a small piece of fabric of a theory which may or may not turn out to be true. But it doesn't mean that thimerosal causes autism. There are lots of fragments, pieces of biological evidence and theories. But those theories are still incomplete."

bmiller@semissourian.com

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