EIF2AK2 and Alzheimer disease: PKR is activated in AD brains (Chang, Suen, et al., 2002; Chang, Wong, Ng, & Hugon, 2002; Hugon, Mouton‐Liger, Dumurgier, & Paquet, 2017; Page et al., 2006; Paquet et al., 2012), and its concentration in the cerebrospinal fluid (CSF) predicts cognitive decline (Dumurgier et al., 2013; Mouton‐Liger, Paquet, Dumurgier, Lapalus, et al., 2012).