Association of 276G>T adiponectin gene polymorphism to plasma adiponectin and albuminuria in type 2 diabetic patients

Purpose The 276G>T polymorphism of the adiponectin (ADIPOQ) gene has been correlated with plasma adiponectin, type 2 diabetes (T2D) and its complications. Studies of the role of 276G>T polymorphism in the prevalence of T2D kidney disease are few and contradictory; ethnic differences might play a role. We aimed to assess the relationship of this polymorphism with albuminuria in a cohort of Caucasian T2D patients. Methods Consecutive T2D outclinic patients were screened and included upon informed consent; exclusion criteria were glomerular filtration rate (GFR) <30 ml/min, acute intercurrent illness and urinary tract infection. History, standard laboratory evaluation, total plasma adiponectin and genotyping for the 276 ADIPOQ locus were obtained. Results One hundred and three T2D patients were included. Forty-three (41.7%) of them had GG genotype, 50 (48.5%) had GT and 10 (9.7%) had TT genotype. Plasma adiponectin was significantly higher in TT-allele carriers (19.03 +/- 3.46 mu g/ml) than in GT (10.14 +/- 1.78 mu g/ml) and GG carriers (8.71 +/- 1.60 mu g/ml), P = 0.003. Adiponectin was higher in albuminuric (13.97 +/- 2.07 mu g/ml) than in normoal-buminuric patients (6.91 +/- 0.88 mu g/ml), P = 0.004. The prevalence of T allele was higher in normo-albuminuric patients [36 (69.2%) GT + TT carriers] than in albuminuric ones [24 (47.1%)], P = 0.02. Logistic regression identified the following as predictors of albuminuria: GG genotype: P = 0.003 (OR 4.2; CI 1.61-10.96); low GFR: P = 0.003 (OR 0.97; CI 0.95-0.99); and high plasma adiponectin: P = 0.012 (OR 1.07; CI 1.01-1.14). Conclusions Our data suggest that 276G>T polymorphism of the ADIPOQ gene is associated with plasma adiponectin levels. By influencing adiponectinemia, 276G>T polymorphism might predict the presence of albuminuria in Caucasian T2D patients.