We analyzed the DNA methylation profiles of PSEN1, IL-1β and IL-6 since these three genes were previously reported to be modulated by the methylation of their 5′-flanking regions in SK-N-BE cells, although in different experimental settings and in the brains of AD subjects vs. healthy age-matched controls [53,54,55,64,65]. The gene discussed is IL6; the disease is Alzheimer disease.