MT-ND4L and Alzheimer disease: The dominant GOBP annotations were mitochondrial metabolic processes, such as oxidative phosphorylation (ER = 27.20, adj.p = 5.47E−04), ATP synthesis-coupled electron transport (ER = 32.53, adj.p = 1.92E−03), and ATP metabolic processes (ER = 12.79, adj.p = 4.0E−3) (Fig. 2b and Supplementary Table 3); consequently, most genes in these pathways were mitochondria-related genes, including mt-Nd4l, mt-Co2, and mt-Nd3, and P5 genes were highly enriched in most cell types of human AD specimens.