HIF3A and gestational diabetes: Of the 62 genes associated with GDM and IGT, eight genes were investigated in two or more studies, of which the increased methylation of HIF3α and PGC1-α and the decreased methylation of PPARα in women with GDM compared to women without GDM were consistent across studies in diverse populations, using different measurement platforms and methodologies, biological material and diagnostic criteria, supporting their involvement in GDM.