The Role of Gene Polymorphisms rs1800629 TNFα and rs1800818 PDGFB in Relapses after Surgical Treatment of Diabetic Maculopathy
Analysis of the literature data indicated the possible role of gene polymorphisms rs1800629 (-308G/A) TNFαand rs1800818 PDGFB in the development of such complications of diabetes mellitus 2 type (DM2T) as diabetic retinopathy (DR) and maculopathy (DMP), which suggested the possibility of its connection to DMP relapses occurrence after surgery. The study included 313 patients with DMP (313 eyes) and initial (n=40), moderate or severe non-proliferative (n=92) and proliferative DR (n=181) stages. Patients underwent posterior subtotal vitrectomy (PSV) (n=78); PSV in combination with inner limiting membrane (ILM) peeling (n=85); PSV with ILM peeling and panretinal laser coagulation (n=81); and PSV with ILM peeling and panretinal laser coagulation and cataract phacoemulsification (n=69). Blood level of TNFα and PDGF-BB before surgical treatment was determined by enzyme immunoassay, polymorphisms - by polymerase chain reaction. For statistical procedures the Statistica 10 program (StatSoft, Inc., USA) was used. Our results and analysis of literature data suggest that the pathogenetic factor contributing to DMP relapses after surgery is a high content of TNFα in carriers of risk minor genotype A/A rs1800629. This genotype determined the development of DMP relapses in 96.9% of its carriers. Carriers of the G/A heterozygote also had an increased risk of relapses. The rs1800818 PDGFB was also associated with DMP relapses, but carriers of mutant genotypes (T/C and C/C) were less at risk than carriers of ancestral T/T genotype. The content of PDGF-BB was lower in the absence of relapses, which could explain the protective effect of this polymorphism. Thus, it can be assumed that both TNFα and PDGF-BB are potential targets for the development of targeted molecular therapy for DMP and its relapses after surgery.