For example, tau reduction prevents behavioural abnormalities in hAPP transgenic mice characterized by the formation of amyloid plaques but not tau aggregates.7,9,62 In neuronal cultures, tau ablation prevents axonal transport deficits caused by Aβ oligomers.14,63 Interestingly, decreasing endogenous tau levels is beneficial in murine models of autism,64 stroke65 and epilepsy9,66,67 despite the lack of abnormal tau, suggesting that this beneficial effect does not directly involve tau aggregation processes. Here, MAPT is linked to autism.