HDAC6 and Alzheimer disease: Genetic ablation of HDAC6 in a transgenic mouse model of AD (APPPS1 mice) was shown to alleviate cognitive deficits without impacting Aβ plaque burden (12); although tau levels were not evaluated, APPPPS1 mice develop p-tau neuritic structures (32), which may indicate that the protective effect of loss of HDAC6 is due to effects on tau.