The only exceptions are the G2/M checkpoint and the Hippo pathway, whose members are significantly decreased in these regions, suggesting that inactivation of this key developmental pathway, possibly via the observed upregulation of CD4431, or altered regulation of associated proteins such as the synaptic scaffolding proteins DLG2, DLG3 and DLG4, all of which are downregulated, is an early event in AD development. Here, DLG4 is linked to Alzheimer disease.