A recent meta-analysis included 32 prospective cohort or case-control studies investigating the relationship between serum iron metabolic markers and GDM, and higher levels of serum iron, ferritin, transferrin saturation, ferritin, and hemoglobin were reported in patients with GDM than in those without GDM, suggesting that high serum ferritin and hemoglobin levels are positively associated with the risk of developing GDM (11). The gene discussed is TF; the disease is gestational diabetes.