PPARG and Infertility: RT-PCR quantitative tests showed a significant upregulation of gene expression of PPAR-γ (P = 0.01), GLUT-1 (P = 0.009) and LDLR (P = 0.03) in PBMCs of infertile women diagnosed with PCOS who were candidate for IVF following vitamin D supplementation rather than placebo (Fig. 2).