IGFBP2 and obesity due to melanocortin 4 receptor deficiency: In this study, the non-targeted high-precision serum proteomics analysis of a cross-sectional discovery cohort with bioinformatics interpretation, literature research and biostatistical assessment, identified a novel sexually dimorphic correlation of IGFBP-2 and IGFBP-3 with vitamin D status in non-diabetic males and females with obesity (Fig. 4a).