Objective  To investigate the expressions of uncoupling protein 3 (UCP3) gene and plasma cell membrane protein-1 (PC-1) gene in patients with type 2 diabetes mellitus (T2DM) complicated with obesity.

  Methods  The clinical materials of 120 T2DM patients with obesity, 120 T2DM patients without obesity, 120 obese patients and 120 non-T2DM and non-obese healthy people were collected from June to December 2018 in authors' hospital. The genotypes of UCP3Tyr210Tyr (C-T) polymorphism and 121 glutamine in exon 4 of PC-1 gene were detected by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The indexes such as waist hip ratio (WHR), blood pressure, serum total cholesterol (TC), fasting blood glucose (FBG) and 2 h postprandial blood glucose (2 hPG) were recorded, and the related genotypes were detected.

  Results  Non-T2DM & non-obese healthy group showed significant differences compared with obese group (x²=6.452, RR=5.290, P=0.016), T2DM without obesity group (x²=4.658, RR=4.260, P=0.028), and T2DM complicated with obesity group (x²=10.982, RR=9.280, P=0.002). In the people with T2DM and obesity, the relative risk of obesity in cases with Q allelic gene of PC-1 was 9.28 times higher than that in people with non-T2DM and non-obesity.

  Conclusion  There is no correlation between UCP3 gene and T2DM complicated with obesity. The Q allelic gene of PC-1 gene is a susceptible gene of insulin resistance. Therefore, early diagnosis should performed for T2DM patients with family history of obesity. The physicians should guide them to change their lifestyle to improve the prognosis of patients.