Autism Spectrum Disorder (ASD) is considered a multifaceted neurodevelopmental disorder. The last two decades showed an increase in its prevalence until reached about 1 in 54 children. Autistic symptoms may be exacerbated when the interaction of the genetic and the environmental risk factors occur, suggesting that gene-environment interaction could be a mechanism underlying the aetiology of ASD. Aluminium is a known neurotoxic metal that has known health effects in humans. Glutathione-S-transferase (GST) genes and their enzymes play a major role in the detoxification of many toxic metals. Data were collected from 76 children aged 2-8 years diagnosed with ASD and 30 sex and age matched healthy children. The aim of this study was to investigate the association of polymorphisms in the two GST genes (GSTM1 and GSTT1) with mean aluminium concentrations (as, gene-environment interaction) and oxidative status markers (GST enzyme, malondialdehyde and nitric oxide) among the studied groups. The study started at December 2019 and last for one year at the clinics of National Research Centre, Egypt. The results of this study showed that the null GSTM1 and GSTT1 genotype is the most common type in ASD and that genotype may predispose ASD children to decreased antioxidant status (GST enzyme activity) which in term lead to mal detoxification of aluminium. There is marked increase in aluminium concentrations in hair of ASD children and oxidative markers (increase in MDA and NO) leading to oxidative damage that may play an important role in children autistic status. The study recommends adding antioxidant supplements to daily diet of ASD children to improve their antioxidant status and in term improving management of patients with autism spectrum disorders. Further studies are needed to describe other GST gene polymorphisms.

Background:Recently, several studies showed oxidative stress in autism spectrum disorder (ASD) patients. Another study found oxidative stress state and mal detoxification of aluminum in autistic children. Zinc, vitamin C and vitamin E may play a significant role in the detoxification and overcoming the oxidative stress among children with autistic disorder. Objectives: A clinical trial was designed to evaluate the role of vitamin E, vitamin C and zinc oral supplementation on the oxidant-antioxidant status and the aluminum level among autistic children. Methods: Hair aluminum level (Al), malondialdehyde (MDA), Nitric Oxide (NO) and Glutathione S-Transferase (GST) activity, were estimated in 30 autistic children before and after vitamin E, vitamin C and zinc supplementation for three months. Results: After supplementation, the results revealed that hair aluminum level, MDA and NO of the children were significantly decreased. While, GST activity was significantly increased. In addition, the study showed improvement in childhood autism rating scale (CARS) score after antioxidant supplementations. As before supplementation, 7.8% of children were scored mild, 51.4% were scored moderate, and 40.8% were scored severe. While, after supplementation there were not any sever cases observed between examined children. Conclusions: Antioxidant supplementation through vitamin E, vitamin C and zinc apparently improved antioxidant status against oxidative stress among ASD children. This improvement in antioxidant status help in decreasing of aluminum level in autistic children with decreasing oxidative stress biomarkers (MDA, NO) and increasing detoxification enzyme (GST), which in turn leads to an improvement in childhood autism rating scale (CARS) score of autistic children. Thus, antioxidant supplementation may help as a protective supplementation from susceptibility to autism development in children with high aluminum level.