The rate of reported autism cases has risen by 25%! What is occurring within our environment that may be contributing to this phenomenon?
Scientists had long estimated that 90 percent of autism risk was genetic and 10 percent reflected environmental factors. But a 2011 study of twins by scientists at Stanford University concluded that genes account for 38 percent of autism risk and environmental factors 62 percent.
Exactly what those factors are, however, remains the subject of intense research, with two large studies funded by the National Institutes of Health examining everything from what the mother of a child with autism ate during her pregnancy to what cleaners were in the house and what pollutants were in the dust.
“There is not a clear front-runner” among possible environmental causes of autism, said Craig Newschaffer, chair of the Department of Epidemiology and Biostatistics at Drexel University School of Public Health and lead investigator of one of the NIH-sponsored studies.
There is, however, what he called “good evidence” that any environmental culprit is present during the second or third trimester, the peak of synapse formation. Scientists believe that faulty brain wiring underlies autism.
(Reuters) – About one in 88 children in the United States has autism or a related disorder, the highest estimate to date and one that is sure to revive a national argument over how the condition is diagnosed and treated.