Increased expression of the Wnt antagonist dickkopf-related protein 1 (DKK1), malfunctioning of the Wnt coreceptor low-density lipoprotein receptor–related protein 6 (LRP6), and activation of glycogen synthase kinase-3β (GSK-3β) have all been shown in AD brains. Here, GSK3B is linked to Alzheimer disease.