T2DM patients with magnesium deficiency exhibited higher levels of fasting glucose (11.2 ± 3.9 mmol/L), HbA1c (8.6 ± 2.1 mmol/L), and triglycerides (2.1 ± 0.9 mmol/L), along with increased insulin resistance (Homeostatic Model Assessment of Insulin Resistance = 6.6) and decreased insulin sensitivity (Quantitative Insulin Sensitivity Check Index = 0.29). The gene discussed is INS; the disease is magnesium deficiency.