In the reconstructed AD variant-variant PPI network, we observed that the ESR1 gene interacts with several susceptibility genes, including UBE2I, TP53, SETD7, RPS6KB2, PPARG, PARP1, NTRK1, NOS3, MMP9, MAPK1, IGF1, ESR2, EGFR, DROSHA, CTSD, CD44, BRCA2, BCL2, and AKT1 (Figure 11). This evidence concerns the gene UBE2I and Alzheimer disease.