Cluster 4, which contained the APP protein, a hallmark of AD pathogenesis, was enriched for processes and components known to be biologically important in AD, including the lysosome (p = 2.7E−6), glycosaminoglycan degradation (p = 1.1E−3), and the complement and coagulation cascades (p = 6.5E−3) (Fig. 3b). The gene discussed is APP; the disease is Alzheimer disease.