system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Age of Onset, Amino Acid Substitution, Case-Control Studies, Diabetes Mellitus, Type 1, Diabetic Retinopathy, Female, Gene Frequency, Genetic Carrier Screening, Genetic Markers, Glutathione Transferase, Glycated Hemoglobin A, Humans, Male, Polymerase Chain Reaction, Polymorphism, Genetic, Reactive Oxygen Species, Reference Values, Superoxide Dismutase, Young Adult.
user
Are genetic polymorphisms in genes encoding antioxidant enzymes associated with diabetic retinopathy in type 1 diabetes? Context: Oxidative stress plays an important role in the development of microangiopathic complications in type 1 diabetes. We investigated polymorphic markers in genes encoding enzymes regulating production of reactive oxygen species in association with diabetic retinopathy or diabetic nephropathy. A total of 124 patients with type 1 diabetes were investigated in this case-control study. All subjects were matched for sex, age, and duration of diabetes. Genotyping was conducted using real-time PCR for p.Val16Ala polymorphism in the MnSOD gene and c.C-262T in the promoter region of the CAT gene. Multiplex PCR method was used for determination of GSTM1 and GSTT1 polymorphic deletions. Fluorescence-labeled PCR amplicons and fragment analysis was used for assessing the number of pentanucleotide (CCTTT)n repeats in inducible nitric oxide synthase. A positive association of MnSOD genotype Val/Val (odds ratio [OR] 2.49, 95% CI 1.00-6.16, P = 0.045) and GSTM1-1 genotype (2.63, 1.07-6.47, P = 0.031) with diabetic retinopathy but not with diabetic nephropathy was demonstrated. Additionally, the combination of the two genotypes conveyed an even higher risk (4.24, 1.37-13.40, P = 0.009). No other investigated genetic polymorphisms were associated with either diabetic retinopathy or diabetic nephropathy.
assistant
Selected polymorphisms in genes encoding MnSOD and GSTM1 could be added to a panel of genetic markers for identification of individuals with type 1 diabetes at an increased risk for developing diabetic retinopathy. Final Decision: yes