Association Of Mutation And Polymorphism Of Endothelial Nitric Oxide Synthase Gene With Type 2 Diabetes Mellitus And Microvascular Complications

Objective To investigate association of mutation and polymorphism of endothelial nitric oxide synthase gene with type 2 diabetes mellitus, diabetic nephropathy, diabetic retinopathy. Methods The genotypes ofendothelial nitric oxide synthase gene (G894T mutation at exon 7 and 4A/B 27-bp tanden repeat polymorphism at 4 intron) were determined by polymerase chain reaction-restriction fragment-length polymorphism analysis in 399 type 2 diabetic patients(2-DM),54 impaired glucose tolerance patieiits(IGT), 113 normal glucose tolerance control suhjects(NGT) in Chinese people in Hefei region. Type 2 diabetic patients were divided into four groups defined by urine alhuniium excretion rate which consisted of normal urine albumium excretion rate group(42),micro-urine aI bumiurn excretion rate group(85),cI mica! diabetic nephropathy group(24)and end-stage renal disease group(13).We also divided type 2 diabetic patients into three groups defined by examination of direct ophthalmoscopy which consisted of diabetes without retinopatliy(56),with simple tetinopathy(90)and with proliferate retinopathy (12).We compared the genotypes frequency and allele frequency among groups. Results We found no statically significant difference of genotypes frequency and allele frequency of eNOS gene among 2-DM,IGT and NOT groups.There were statically significantly different genotypes frequency and allele frequency of 4A/13 polymoiphism of eNOS gene in three diabetic groups defined by ophthalmoscopy and NGT group. The eNOS A allele frequency was higher in proliferate retinopathy group than in two other groups(p=O.007).We found statically significantly different genotypes frequency and allele frequency of G894T mutation of eNOS gene in four diabetic groups defined by urine albumium excretion rate and NGT group. The eNOS T allele 2 frequency was higher in end-stage renal disease group than in three other groups(p=O.008). Conclusions These results imply that in Chinese people in Hefei region 4A/B polymorphism of eNOS gene may be associated with diabetic retinopathy A allele may be a risk factor of diabetic retinopathy. We did not found enough. association with the polymorphism and diabetic nephropathy. G894T mutation of eNOS gene may be associated with diabetic nephropathy. I allele may be a risk factor of diabetic nephropathy. The mutation may be not associated with diabetic retinopathy. We did not found association with the G894T mutation, 4A/B polymorphism of eNOS gene and type 2 diabetes mellitus. The two markers might not play a role in happen of type 2 diabetes mellitus...