As with genes, it’s likely that more than one environmental factor is involved in increasing risk for ASDs. Heavy metals, parental age, immunological proteins, environmental pesticides and insecticides, and food contaminants are thought to act as modulators of ASDs.
Epigenetic mechanisms, which function at the interface between genetic and environmental factors, provide researchers with many new ways to study how disorders like ASD develop and possibly change over time. For example, several areas on chromosomes, which are hot spots for genomic imprinting, are found to be located on loci 7q and 15q that are highly affected in individuals with ASDs. In addition, DNA methylation is an important regulator for ASDs. It is indicated that mutations in methyl-CpG binding protein 2 (MeCP2) cause Rett syndrome with characteristic autistic-like behavior in addition to seizures, ataxia, and stereotypic hand movements. Besides, MeCP2 also regulates several genes related to synaptic plasticity, neuronal cell proliferation and neuronal transcription factors. Precisely because epigenetic misregulation of synaptic genes may contribute to ASDs, extrinsic factors like the environment or drugs can alter epigenetic make up leading to defective neuronal functions.
We believe that children make significant developmental gains with early and intense intervention. I hope that everyone can give these children more care.