SLC30A1 and obesity due to melanocortin 4 receptor deficiency: Obesity showed a significant upregulatory effect on ZNT1 expression by two-way ANOVA analysis (p = 0.0177; subgroup analysis examining lean PCOS vs. obese PCOS, and lean controls vs. obese controls using Student’s t-test; p = 0.0169 and p = 0.2489, respectively).