Analysis of T-786C and 4a/b endothelial nitric oxide synthase gene polymorphisms in retinopathy of prematurity

Abstract

Retinopathy of prematurity (ROP) is a vascular proliferative disorder of retina, that causes visual impairment in premature children. Beside well known risk factors such as short gestational age, low birth weight and early oxygen exposure, genetic susceptibility is considered as a risk factor for development of the disease. The aim of our study was to explore the association of T-786C and 4a/b eNOS gene polymorphisms with the development of severe ROP. Study included 174 preterm infants, 84 with ROP and 90 as a control group. No differences have been observed in genotypes and alleles distributions of eNOS T-786C and eNOS 4a/b polymorphisms between two analyzed groups. There was significant difference in female infants by dominant model for 4a/b genotypes (4bb/4ba+4aa). Namely, female infants in ROP group were more frequently carriers of 4ba and 4aa genotypes than female infants in control group (p=0.037). Analysis of association between 4a/b eNOS polymorphism and ROP among preterm infants have not shown statistically significant association (p=0.288). Gestational age values by recessive model (4bb+4ba/4aa) were significantly lower in infants with 4aa genotype (t=2.034 p=0.044). Almost all detected 4aa genotypes were present in the group of infants with gestational age under 30 weeks (p=0.032), but multivariate linear regression analysis does not show association of 4a/b genotypes with gestational age of premature infants. According to results of the present study T-786C and 4a/b polymorphisms of the eNOS gene may not be the risk factors for the manifestation of severe ROP in Serbian infants.