GSTM1 and gestational diabetes: Similar to this, we found that rs6632677 particularly affected the risk of GDM in SBP > 110.2 mmHg, FPG ≤ 4.77 mmol/L, and Hb ≤ 5.15 mg/dl subjects, and significant interaction effects between rs6632677 and SBP and FPG were detected.