Vitamin D affects insulin secretion and sensitivity, maintains glucose tolerance, enhances calcium absorption in the duodenum and kidneys, and thus activates intracellular signaling in the insulin cells, thereby affecting glucose homeostasis, so when vitamin D is insufficient or deficient, the risk of developing diabetes during pregnancy increased (Hu et al., 2018; Xuan et al., 2013). The gene discussed is INS; the disease is diabetes mellitus.