Your Medical Detective
Ronald Grisanti D.C., D.A.B.C.O., D.A.C.B.N., M.S.
Autism has reached epidemic proportions and it appears medical science has yet to find a definitive cause. According to the Centers for Disease Control and Prevention, approximately 1 in 88 children suffer from an autism spectrum disorder (ASD), and the condition is nearly five times more likely to occur in boys than in girls.
Although some believe that genetics and/or environmental factors may play a role, the verdict is still out there.
Now, a new study, published in the journal PLOS Computational Biology, has revealed that toxins in the environment may play a much more significant role in the formation of this neurodevelopmental disorder than previously thought.
Researchers of this study from the University of Chicago examined medical records from more than 100 million people living in the United States. Their analysis revealed that autism and intellectual disability (ID) rates correlated with incidences of genital malformations in newborn males.
According to these researchers, this association is an indicator of exposure to harmful environmental factors during congenital development.
According to Andrey Rzhetsky, a professor of genetic medicine and human genetics at the University of Chicago, and one of the study’s authors, he discovered that during pregnancy there are certain sensitive periods where the fetus is very vulnerable to a range of small molecules. These molecules come from things like plasticizers, prescription drugs and environmental pesticides. Essentially these small molecules alter normal development.
To conduct the research, Rzhetsky and his team carefully studied and analyzed data from insurance claims from individual states and more than 3,100 counties. They basically compared autism rates and cases of congenital malformations of the male reproductive system – such as micropenis, hypospadias (urethra on the underside of the penis), undescended testicles and more.
What was astounding was the fact that the researchers found that autism rates increased by 283 percent for every 1 percent increase in frequency of congenital malformations while intellectual disability rates increased by 94 percent for every 1 percent increase.
Rzhetsky concluded that malformations predict very strongly the rates of autism, and the rate of malformation per person varies significantly across the country.
The association was much stronger in boys, as male children with autism were almost six times more likely to have congenital malformations.
Although the medical community claims that there is no definitive cause for autism, Rzhetsky hopes his study will ignite a shift in the scientific community from researching mostly genetic causes to researching more environmental factors.
According to Rzhetsky, the takeaway is that the environment may play a very significant role in autism, and we should be paying more attention to it.
Reference:
Rzhetsky, Bagley, Wang, Lyttle, Cook, Altman, Gibbons, Environmental and State-Level Regulatory Factors Affect the Incidence of Autism and Intellectual Disability, PLOS Computational Biology, March 13, 2014