HOTAIR and Alzheimer disease: Since H3K27me3 and H3K4me3 are involved in the DNA damage response and are associated with AD 169, 314, 367, it is conceivable that HOTAIR may play a role in the DNA damage response and AD pathogenesis by coordinating the levels of H3K27ac, H3K27me3, H3K4me3 and other epigenetic markers on the bivalent promoters by recruiting REST and PRC2 351.