The maternal effect in infantile autism: Elevated DNA damage degree in patients and their mothers

Infantile autism is a common disorder of mental development; besides hereditary predisposition, various environmental factors, including the condition of the mother’s body during pregnancy (“maternal effect”), have a significant impact on its appearance. Oxidative stress is suggested to play a key role in the pathogenesis of infantile autism. It causes a prominent genotoxic effect, which is realized through appearance of single and double strand breaks of the nuclear DNA. In patients with infantile autism and their mothers we evaluated the degree of DNA damage by using the DNA comet assay and determining the comet tail moment and DNA percent ratio in the tail. These two parameters demonstrated strong correlation (r = 0.90). Mean and median values of both parameters were significantly higher in samples from autistic children, than in agematching healthy controls. Interestingly, these parameters were also higher in healthy mothers of autistic children and they did not differ from the values in the group of autistic children. In the control group of healthy women of reproductive age, who had no children with autism, the mean value of the DNA comet tail moment significantly differed from the group of mothers of autistic children, but not from the control group of healthy children. The results suggest that mentally healthy mothers of autistic children have some genotoxic factors, which can determine development of the pathological process in the fetus via the environmental “maternal effect” during gestation.