The etiological effect and genetic risk of +252 A/G variant of TNF‐β gene related to the susceptibility of urinary tract infection in a sample of Iraqi patients with type 2 diabetes: A case control study

BACKGROUND AND AIM: Urinary tract infection (UTI) is the most common infection in type 2 diabetes patients. TNF‐β is a cytokine with multiple functions in immunomodulatory and inflammatory mechanisms. The variation at position +252 A/G of TNF‐β impacts both gene expression and plasma concentration of TNF‐β proteins. The findings may shed light on the genetic factors that predispose diabetic patients in Iraq to UTIs. METHODS: A total of 200 individuals were divided into 100 patients with type 2 diabetes, categorized according to UTI, and 100 control subjects. Genetic analysis of +252 A/G of the TNF‐β gene was carried out using the TaqMan probe allele discrimination method. The level of TNF‐β was estimated by the ELISA technique. RESULTS: In the recessive model (GG vs. AA/AG) of TNF‐β + 252 A/G in T2D/UTI patients compared to controls, a significant association p = 0.029 (OR: 2.8; CI 95% = 1.14–7.09): E = 15.6% was observed. Furthermore, in T2D patients without UTI, the dominant model AA versus AG/GG was associated with a preventive role P: 31.3% (OR: 0.4; CI 95% = 0.22–0.88) and a p value = (0.02). Overall, AG proportions showed a high level of TNF‐β within the control group p = 0.03, while all proportions of the +252 A/G showed significant differences in TNF‐β level between groups p ≤ 0.05. Pearson's correlation analysis observed a link between TNF‐ levels, fasting plasma glucose (FPG), and HbA1c. CONCLUSION: In T2D patients, the G allele may be linked to a higher probability of UTI, as well as an increased level of TNF‐β in a genotype‐dependent manner.