For the SNAP23 gene, negative associations were found between rs112568544 and the patients with PCOS and depression in the additive genetic model (OR = 0.39, 95% CI: 0.17–0.92), the dominant genetic model (0.34, 0.14–0.83), the co-dominant genetic model (0.32, 0.13–0.80), and the over-dominant genetic model (0.32, 0.13–0.79). This evidence concerns the gene SNAP23 and major depressive disorder.