New insight into the pathogenesis of retinopathy of prematurity: assessment of whole-genome expression

Abstract

Retinopathy of prematurity (ROP) is one of the most common preventable causes of blindness and impaired vision among children in developed countries. The aim of the study was to compare whole-genome expression in the first month of life in groups of infants with and without ROP. Blood samples were drawn from 111 newborns with a mean gestational age of 27.8 wk on the 5th, 14th, and 28th day of life (DOL). The mRNA samples were evaluated for gene expression with the use of human whole-genome microarrays. The infants were divided into two groups: no ROP (n = 61) and ROP (n = 50). Overall, 794 genes were differentially expressed on the 5th DOL, 1,077 on the 14th DOL, and 3,223 on the 28th DOL. In each of the three time points during the first month of life, more genes were underexpressed than overexpressed in the ROP group. Fold change (FC), which was used in analysis of gene expression data, ranged between 1.0 and 1.5 in the majority of genes differentially expressed. Pathway enrichment analysis revealed that genes in four pathways related to inflammatory response were consistently downregulated due to the following variables: ROP and gestational age.