Association of IL16 rs11556218 and IL1B rs16944 polymorphisms with type 2 diabetes in the Kinh Vietnamese population.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a multifactorial metabolic disease in which inflammatory mechanisms are involved in disease development and progression. Polymorphisms in cytokine-related genes may influence susceptibility to T2DM, yet evidence in Vietnamese individuals remains scarce. This study was designed to investigate whether IL16 rs11556218 and IL1B rs16944 are associated with T2DM in Kinh Vietnamese adults. METHODS: An analytical cross-sectional unmatched case-control study was conducted in 392 unrelated Kinh Vietnamese individuals, including 196 patients with T2DM and 196 non-diabetic controls, recruited at Cho Ray Hospital, Ho Chi Minh City, between February and August 2025. Peripheral blood samples were collected for genomic DNA extraction. Genotyping of IL16 rs11556218 and IL1B rs16944 was performed using TaqMan SNP Genotyping Assays. Hardy-Weinberg equilibrium was assessed in the control group. Associations between the investigated polymorphisms and T2DM were analyzed under codominant, dominant, recessive, and log-additive models, with adjustment for body mass index (BMI), waist-to-hip ratio (WHR), and family history of diabetes. RESULTS: Both polymorphisms satisfied the Hardy-Weinberg equilibrium in the control group. For IL16 rs11556218, significant differences in allele and genotype frequencies were observed between patients and controls, and the G allele showed a nominal association with lower odds of T2DM. After adjustment for BMI, WHR, and family history of diabetes, the TG genotype showed a nominal association with lower odds of T2DM in the codominant model (adjusted OR = 0.56, 95% CI: 0.32-0.98; nominal P = 0.026). Nominal associations were also observed in the dominant model (adjusted OR = 0.52, 95% CI: 0.30-0.89; nominal P = 0.016) and the log-additive model (adjusted OR = 0.52, 95% CI: 0.32-0.85; nominal P = 0.0081). For IL1B rs16944, genotype distribution likewise differed between the two groups. Under the recessive model, the CC genotype showed a nominal association with higher odds of T2DM after adjustment (adjusted OR = 2.13, 95% CI: 1.20-3.79; nominal P = 0.0089). None of these associations met the Bonferroni-corrected significance threshold of P < 0.00625. Compared with controls, participants with T2DM had higher BMI and WHR, higher triglyceride levels, lower HDL cholesterol, higher fasting plasma glucose and blood pressure, and more commonly reported a family history of diabetes. CONCLUSIONS: IL16 rs11556218 and IL1B rs16944 showed nominal associations with T2DM in this sample of Kinh Vietnamese adults, although none remained statistically significant after Bonferroni correction. These exploratory findings require confirmation in larger independent studies before any firm conclusions regarding their biological or clinical relevance can be drawn.