Abstract
Purpose:
To identify the gene variants that are associated with diabetic retinopathy (DR) by meta-analysis.
Methods:
PubMed, EMBASE and EBM Cochrane Library were used for comprehensive electronic search, which was supplemented by hand-searching. All case-control (or cohort) studies were included. Two reviewers independently screened all the reports and extracted relevant data. Meta-analyses were conducted with ‘metafor’ package in R (v2.15.0) and Stata (v11 StataCorp, USA). Tests for heterogeneity, publication bias, small-study effects, and subgroup analysis were used to clarify the potential bias.
Results:
Totally 4724 reports on DR genetics were yielded, 347 were genetic association studies. More than 200 genes and 430 variants have been associated with DR with inconclusive results. Among them, 56 reports were on 90 variants of 9 genes attributed to inflammatory responses and oxidative stress, which have received much attention in the past 5 years. The pooled data showed a single nucleotide polymorphism (SNP; codominant, OR=0.43; 95% CI: 0.23-0.82) of the AGER gene was protective against DR. High-risk alleles included variants in NOS2 (OR=0.16, 95% CI: 0.03-0.71), SERPINF1 (OR=1.23, 95% CI: 1.01-1.49), and TNFB (OR=1.62, 95% CI: 1.05-2.49). After eliminating heterogeneity in subgroup analysis, the AGER SNP showed opposite effects in Chinese+Japanese (OR=0.25, 95% CI: 0.13-0.5) and Indian (OR=1.8, 95% CI: 1.31-2.48). A SNP of the ICAM1 gene was related to DR only in the Chinese and Japanese populations (OR=2.59, 95% CI: 1.51-4.46).
Conclusions:
Results of our meta-analyses support the involvements of variants in AGER, SERPINF1, ICAM1 and TNFB in DR. Substantial population differences in DR genetics are also indicated.
Keywords: 499 diabetic retinopathy •
539 genetics