Postmortem studies in patients with Alzheimer’s disease, Parkinson’s disease, progressive supranuclear palsy, and ALS [29,30,31] reveal markers of UPR activation, including phosphorylation of PERK and eIF2α associated with protein aggregates [32,33] (Figure 1). The gene discussed is EIF2AK3; the disease is early-onset autosomal dominant Alzheimer disease.