The importance of the polymorphism of the AT1-receptor gene in diabetic nephropathy patients
Melinda Kolcsar1 & Emoke Endreffy2
Objective of our study was to investigate the renoprotective efficacy of valsartan and enalapril depending on the genetic polymorphisms of the angiotensinic system.
Material and methods: In 32 type 2 diabetic patients with microalbuminuria, DNA extraction and genotypization were performed. The studied polymorphism was A1166C of the AT1-receptor gene. Two types of antiangiotensinic drugs were used in order to reduce microalbuminuria: enalapril (20 mg/d) and valsartan (80 mg/d). The evaluation period was 6 months for both type of drugs. A 28 days wash-out period was insert when drugs were changed between groups. On the end of the study the grade of microalbuminuria reduction and normalbuminuria attain were evaluated and compared depending on genotypes.
Results: Using light cycler technology three genotypes of the angiotensin-receptor gene A1166C polymorphism were obtained: the AA, AC and the CC one. In the patients with CC genotype reduction of microalbuminuria was significantly lower than in other patients and normalbuminuria attain was absent.
Conclusion: CC genotype of the AT1-receptor gene polymorphism represents a risk factor of resistancy in type 2 diabetic nephropathy treatment with antiangiotensinic drugs.