Through down-regulating the expression of DNMT1, miR-152 reduced GDM and the activity of DNMT to reactivate the lactation signal transduction genes Akt and Pparγ. In addition, miR-152 significantly altered the viability of the DCMECs as well as the secretion of β-casein, triglyceride and lactose. The gene discussed is DNMT1; the disease is gestational diabetes.