Relationship of rs1800470 polymorphism of TGFB1 gene with diabetic retinopathy in type 2 diabetes

Purpose: To investigate the relationship between rs1800470 polymorphism of TGFB1 gene and diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM).Material and Methods: Totally, 102 type 2 diabetes (T2DM) patients with DR were examined and divided into groups based on the stage of DR: group 1 (non-proliferative DR (NPDR), 35 patients), group 2 (pre-proliferative DR (PPDR), 34 patients), and group 3 (proliferative DR (PDR), 33 patients). The control group was composed of 61 individuals. Patients underwent a routine eye examination. rs1800470 (Т869С; L10P) genotypes were determined by real time polymerase chain reaction (PCR) using Gene Amp® 7500 PCR System (Applied Biosystems, Foster City, CA) and TaqMan Mutation Detection Assays (Life Technologies, Carlsbad, CA). Results: The ancestral GG genotype tended to be less frequent, whereas the minor AA genotype (and, correspondingly, the minor A allele) tended to be more frequent in patients with DR compared with controls. The minor AA genotype and, consequently, the minor A allele were more frequent in patients with a more severe DR, but the difference was not significant (р > 0.05). We found an association of rs1800470 genotype with the phenotype of DR: BCVA was lower (р = 0.016) and CRT and CRV were larger (р < 0.001 for both comparisons) in carriers of the minor AA genotype of rs1800470 compared to carriers of the ancestral GG genotype. After stratification of patients by the stage of DR, the greatest distinction in parameters among carriers of different genotypes was seen in PDR: in carriers of the AA genotype, CRT and CRV were 2.5 times and 1.4 times, respectively, larger, than in carriers of the GG genotype (p < 0.001).Conclusion: rs1800470 polymorphism of TGFB1 gene affected the course of DR, which was more pronounced in PDR.