APOE and Alzheimer disease: Based on the criteria described above, hub genes in six mitochondrial/AD trait-related modules were screened out (lightsteelblue1-MMSE/APOE2: 3, pink-ABETA: 170, thistle2-PTAU: 1, violet-AGE: 3, darkgreen-DX: 31, and cyan-APOE4: 51).