The association between diabetic nephropathy and polymorphisms in PPARγ Pro12Ala and CCR5δ 32 genes in type 2 diabetes

Background Diabetic nephropathy is one of the debilitating complications of type 2 diabetes and the leading cause for end-stage renal disease requiring renal replacement therapy. Currently identified risk factors do not fully explain the susceptibility of some patients to diabetic nephropathy. Peroxisome proliferator-activated receptor γ (PPARγ) Pro12Ala gene polymorphisms modulate insulin sensitivity and oxidative stress in diabetic patients, and conflicting data exist on its association with kidney disease in diabetes. Several polymorphisms in another immune modulator set of genes, the C-C chemokine receptor 5 (CCR5) genes, were associated with diabetic nephropathy. However, CCR5δ 32 gene polymorphisms were not studied in patients with diabetic nephropathy. The aim of this study was to assess the association between polymorphisms in both PPARγ Pro12Ala and CCR5δ 32 genes and the presence of diabetic nephropathy in Egyptian patients with type 2 diabetes. MethodsWe included 51 patients having type 2 diabetes for at least 5 years. They were all normotensive patients selected from the outpatient clinic with no other clinically identifiable risk factor for kidney disease. Genotype detection for PPARγ Pro12Ala and CCR5δ 32 gene polymorphisms was carried out using the PCR technique. Clinical data, HbA1c levels, lipid profile, and fasting and postprandial blood sugar levels were recorded. Serum creatinine levels and the urinary albumin/creatinine ratio were measured to stratify the participants according to the presence or absence of diabetic nephropathy. Results Age, sex, BMI, HbA1c, and duration of diabetes were not significantly different among patients with and those without diabetic nephropathy. Diabetic nephropathy patients had a significantly higher urinary albumin/creatinine ratio and lower estimated glomerular filtration rate levels (P