Both EWS:FLI1 and EWS:ERG in EwS, and aberrantly expressed ERG in PCa can bind to GGAA repeats in the promoters and enhancers of coding genes and within microsatellites, causing widespread chromatin remodeling and transcriptional rewiring (5, 6, 9–13). The gene discussed is ERG; the disease is posterior cortical atrophy.