In the crude model, a positive interaction was observed between TC genotype of MC4R and CSI on depression (β = 0.30, CI = 0.04, 0.56, P = 0.023), and DASS-21 (β = 0.62, CI = − 0.32, 1.27, P = 0.062). The gene discussed is MC4R; the disease is depressive disorder.