The GAD enrichment analysis of 81 overlapping common gene functions showed that 35 genes (CDKN1A, CDKN1B, LHB, SERPINE1, KLK3, KLK2, NR3C1, CYP19A1, CYP17A1, CASP9, CCND1, PLAU, CDH1, MYC, DNMT3B, CYP1B1, CD14, NCOA2, NOS2, EGF, UGT2B15, IGF1, ESR1, ESR2, GNMT, VEGFA, AR, IL1B, SELENOP, CYP1A1, BCL2, ID3, PPARA, SHBG, TP53) have the highest significance value (1.54 × 10−27) in their association with PCa. The gene discussed is ID3; the disease is posterior cortical atrophy.