The BTG1-correlated genes were involved in cell adhesion, chemokine, T cell receptor and PD-L1 signal pathways for gastric cancer, endocytosis, infection-related diseases, and spliceosome, ubiquitin-mediated proteolysis and PD-L1 signal pathway for lung cancer, cytokine-cytokine receptor interaction, chemokine, JAK-STAT, FoxO and TNF signal pathway for breast cancer, endocytosis, cAMP, oxytoxin, cGMP and GnRH signal pathways for ovarian cancer. The gene discussed is GNRH1; the disease is breast cancer.