Figure 1.

Overlap of dysregulated genes identified from CpG island microarray and global gene expression profiling previously performed using the same samples. A) Scatter plot shows inverse correlation of log2 ratios of gene expression and methylation of genes with differentially methylated CpG islands directly overlapping with its 5′ end. Inset: plot of log2 ratios of genes with differentially methylated CpG islands located either upstream or downstream of the CpG island. Interestingly, the majority of genes identified from these analyses were hypermethylated in the twins relative to their respective nonautistic siblings, with a corresponding decrease in gene expression. B) Network analysis of 25 genes (circumscribed in blue) that were both differentially methylated and expressed. The network was generated using Pathway Studio 5 network prediction software and identified common biological themes, including apoptosis, cellular differentiation, and inflammation. The analysis also revealed neurologically relevant functions and disorders including synaptic regulation, development, and mental deficiency.