TGF-beta1 gene polymorphism in association with diabetic retinopathy susceptibility: a systematic review and meta-analysis.
BACKGROUND
Transforming growth factor-beta (TGF-β1) gene has been regarded as an important mechanism in angiogenesis, endothelial cell proliferation, adhesion,and the deposition of extracellular matrix. The TGF-β1 gene may be involved in the development of diabetic retinopathy (DR) through disrupting angiogenesis. However, studies investigating the relationship between -509C/T and +869T/C(L10P) polymorphisms and DR yielded contradictory and inconclusive outcomes. In order to realize these ambiguous findings, a meta-analysis was performed to assess the association between the TGF-β1 gene polymorphisms and susceptibility to DR.


RESULTS
We conducted a search of all English reports on studies for the association between the TGF-β1 gene polymorphisms and susceptibility to DR using Medline, the Cochrane Library, EMbase, Web of Science, Google (scholar), and all Chinese reports were identified manually and on-line using CBMDisc, Chongqing VIP database, and CNKI database. The strict selection criteria and exclusion criteria were determined, and odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. The fixed or random effect model was selected based on the heterogeneity test among studies. Publication bias was estimated using Begg's funnel plots and Egger's regression test.


RESULTS
A total of three studies were included in the meta-analysis and all included studies analyzed patients with type 2 diabetes. For +869T/C(L10P) polymorphism, significant association was observed in an allele model (L versus P: OR = 1.34, 95%CI = 1.03-1.73) and the recessive model (LL versus LP+PP: OR = 1.70, 95%CI = 1.13-2.56). As regards -509C/T polymorphism, no obvious associations were found for all genetic models.


CONCLUSIONS
This meta-analysis suggested that the +869T/C(L10P) polymorphism in TGFβ1 gene would be a potential protect factor for DR. However, the -509C/T polymorphism is not associated with DR.
Department of Ophthalmology, The First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China; Department of Epidemiology, School of Public Health, China Medical University, Shenyang City, Liaoning Province, China.
Lei
L
Liu
Department of Anesthesiology, Fengtian Hospital, Shenyang Medical College, Shenyang City, Liaoning Province, China.
Jinghua
J
Jiao
Department of Development and Planning office, China Medical University, Shenyang City, Liaoning Province, China.
Yu
Y
Wang
Department of Ophthalmology, The First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China.
Jingyang
J
Wu
Department of Epidemiology, School of Public Health, China Medical University, Shenyang City, Liaoning Province, China.
Desheng
D
Huang
Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang City, Liaoning Province, China.
Weiping
W
Teng
Department of Ophthalmology, The First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China; Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang City, Liaoning Province, China.
Lei
L
Chen
D003930:Diabetic Retinopathy / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic; D053773:Transforming Growth Factor beta1 / Q000235:genetics*
D053773:Transforming Growth Factor beta1