For example, under ischemic conditions, which cause oxidative stress/DNA damage and are thought to be a prelude to AD 369-371, miR-132 (a neuron-protective microRNA downregulated in AD) expression is selectively silenced in hippocampal CA1 neurons by REST binding to its promoter rich in H3K9ac and H3K4me2 (another bivalent promoter) 352, 372. Here, REST is linked to Alzheimer disease.