Different genetic polymorphisms are associated with different phenotypes on non-proliferative diabetic retinopathy

Abstract

Purpose: To examine the association of different candidate genes with different phenotypes of non-proliferative diabetic retinopathy (NPDR) and risk for development of clinically significant macular edema (CSME).

Methods: A population of 307 diabetic patients with NPDR, followed-up during a 2 years prospective study was classified in 3 different phenotypes of DR progression based on non-invasive methods: Color Fundus Photography (CFP) to assess microaneurysm turnover (MAT) using the RetmarkerDR and Optical Coherence Tomography (OCT) to measure Retinal Thickness (RT). The development of CSME was also addressed. Eleven genes were selected from a list of candidate genes (ACE, AGER, AKR1B1, ICAM1, MTHFR, NOS-1, NOS-3, PPARGC1A, TGFB1, TNF-a, and VEGFA) and their SNPs (174) filtered through bioinformatics tools.

Results: We identified three variants in NOS1 (rs1552228, P=0.022) and AKR1B1 (rs1790998, P=0.010; rs5053, P=0.018) specifically associated with phenotype B. Variants in genes ICAM1 (rs5030400, P=0.041), PPARGC1A (rs10213440, P=0.004) and VEGFA (rs3024994, P=0.011) were specifically associated with phenotype C. Two variants in ICAM1 showed an association with CSME development (rs1801714, P=0.047; rs5498, P=0.035).

Conclusions: Our observations provide a genetic basis to the understanding of mild NPDR and development of CSME suggesting a different pathophysiology for each different phenotype.

Keywords: 499 diabetic retinopathy • 539 genetics