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UC Davis Study Authors: Autism is Environmental (Can We Move On Now?)

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I have always said there may be a small percentage of people with autism spectrum disorder (perhaps those with Asperger Syndrome) whose symptoms are a result only of their genetic makeup, with no environmental factors involved at all.

But a new study out of UC Davis' MIND Institute says that it's time to abandon science's long, expensive, and not very fruitful quest to find the gene or genes that cause autism alone, without any environmental triggers.

"We need to keep (environmental) studies going," Irva Hertz-Picciotto, the co-author of the study and professor of environmental and occupational health and epidemiology at UC Davis, said in a statement.

"We're looking at the possible effects of metals, pesticides and infectious agents on neurodevelopment," Hertz-Picciotto said. "If we're going to stop the rise in autism in California, we need to keep these studies going and expand them to the extent possible."

Autism is predominantly an environmentally acquired disease, the study seems to conclude. Its meteoric rise, at least in California, cannot possibly be attributed to that shopworn mantra we still hear everyday, incredibly, from far too many public health officials: It's due to better diagnosing and counting.

The autism epidemic is real, and it is not caused by genes alone: You cannot have a genetic epidemic. It really is time that we, as a society, accept that cold, hard truth.

"It's time to start looking for the environmental culprits responsible for the remarkable increase in the rate of autism in California," Dr. Hertz-Piccotto said.

The study results suggest that "research should shift from genetics, to the host of chemicals and infectious microbes in the environment that are likely at the root of changes in the neurodevelopment of California's children," the statement added.

The UC Davis Study, funded in part by the National Institute of Environmental Health Sciences (NIEHS) found that the rate of autism among six-year-olds in California mushroomed from less than 9 per 10,000 among the 1990 birth cohort, to more than 44 per 10,000 for kids born in 2000.

This increase, "cannot be explained by either changes in how the condition is diagnosed or counted," the statement said, "and the trend shows no sign of abating."

(It is important to keep in mind that almost every child born in 2000 would have received many vaccines that contained the mercury preservative thimerosal, which was not completely phased out of most - but not all - childhood vaccines until at least 2003.)

Of the 600-to-700 percent increase in autism reported in California between 1990 and 2000, fewer than 10 percent were due to the inclusion of milder cases, the study found, while only 24 percent could be attributed to earlier age at diagnosis.

There was only one logical conclusion: some thing or things in the environment had to be at play here.

I have always said that all environmental factors should be considered in at least some subgroups of autism. This position has been met with considerable ridicule. I believe that opponents are afraid that, if we start looking at toxins like heavy metals, it might one day lead back to thimerosal. Likewise, if we consider live virus triggers, we may have to take another look at the measles-mumps-rubella vaccine (which thousands of parents swear was the trigger than sent their children tumbling into autism).

Now, it's always been easier and more reassuring to tell ourselves that autism was almost purely genetic, that it was always with us at the rate of 1 in 90 men (1 in 60 in New Jersey) and that, gee, weren't doctors doing a great job these days of recognizing and diagnosis this disorder.

This pathetic groupthink has helped create hugely lopsided funding priorities in autism, where genetic studies get lavishly funded, while environmental ones are lucky to even pick up the dollar scraps left behind

"Right now, about 10 to 20 times more research dollars are spent on studies of the genetic causes of autism than on environmental ones," Hertz-Picciotto said. "We need to even out the funding."

I agree.

Yes, we must continue to look for the susceptibility genes that make some kids more vulnerable to environmental triggers - possibly through a diminished capacity to detoxify themselves.

But the sooner our best minds in science and medicine come to grips with the fact that these poor, hapless kids have been exposed to the wrong environmental toxins and/or infectious agents at the wrong time, the sooner we can find out how to best treat what really ails them.

It is illogical for us to oppose the study of, say, mercury exposures and autism, because it might somehow implicate thimerosal, and by extension, vaccines.

After all, heavy metal studies into autism could very well incriminate background environmental sources, but exonerate metal sources found in vaccines, such as mercury and aluminum.

And that would be a good thing for everyone.

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