Role of VEGF, VEGFR and HGF-cMet gene polymorphisms in estimating severity of the disease and requirement of treadment in patients with retinopathy of prematurity

Purpose: The aim of this study was to determine whether there are vascular endothelial growth factor (VEGF), VEGF-receptor (VEGFR-2), hepatocyte growth factor (HGF), HGF-receptor (c-Met) gene polymorphisms in ROP, and to observe the effects of these polymorphisms on the development of ROP, spontaneous regression or progression to threshold disease.Methods: A sample of 123 preterm infants with gestational age ? 34 weeks were prospectively evaluated between December 2006 and February 2009. For genetic analysis, blood samples were collected from each patient and leukocyte DNA was isolated. Genomic DNA was amplified by the polymerase chain reaction (PCR) method with two pairs of primers designed to amplify separately the promotor regions of the VEGF, VEGFR, HGF and c-Met genes. The amplified product was subjected to restriction enzyme digestion or direct sequencing. The infants were divided into 3 groups; ROP requiring treatment (Group 1), spontaneously regressing ROP (Group 2) and no ROP (Group 3).Results: The frequency of VEGF-634G>C polymorphism was 40.5% in group 1, 42% in group 2 and 35.3% in group 3. The frequency of VEGF-460 C>T polymorphism was 59.5% in group 1, 58% in group 2 and 64.5% in group 3. The VEGFR+32G>A (Flk-1+32G>A) polymorphism was identified in 33.3% of infants in group 1, 26% of infants in group 2 and 19.4% of infants in group 3. Our results were similar in all studied groups regarding the association of frequencies of the VEGF-634G>C, VEGF -460 C>T and VEGFR-2 gene promoter polymorphism and the development of ROP, spontaneous regression of ROP and progression to threshold ROP (p:0.840, p:0.840 ve p:0.406, respectively). The carriages of polymorphic allele of VEGF-634G>C, VEGF -460 C>T and Flk-1 +32G>A were not significantly different between the studied groups. HGF and cMet gene promoter polymorphisms did not exist in any of the groups.Conclusion: In our study, the association of the VEGF, VEGFR, HGF and c-Met gene promoter polymorphisms with the risk of development and progression of ROP is weak. We believe that, our study will contribute to reveal the probable genes in the process of predicting the genetic factors releated to ROP, the severity of the disease and the need treatment.