To investigate the relationship between a set of six candidate genes and the risk of diabetic retinopathy (DR) in a cohort of Chinese patients town community with type 2 diabetes mellitus (T2DM).
METHOD A population-based cross-sectional study. Diabetic subjects were recruited from the urban community in Beijing and categorized into groups of proliferative diabetic retinopathy (PDR), non-proliferative diabetic retinopathy (NPDR), or diabetes without retinopathy (DWR) by fundus photography and duration of diabetes.
Six candidate genes, including glycation end certain products receptor sophisticated (AGER), aldose reductase (AKR1B1), inducible nitric oxide synthase (iNOS), pigment epithelium derived factor (PEDF), tumor necrosis factor-alpha (TNF-α), and paraoxonase 1 (PON1), selected by Meta-analysis of genetic association study for DR and biochemical pathways involved in the development of DR. Allele and genotype distribution of 21 functional single nucleotide polymorphisms (SNPs) in their six candidate genes were investigated using the genotype MassARRAY system.
RESULTS Among the 1461 patients with diabetes were recruited from the community, 569 have been selected in the following genotypic analysis, including 97 patients with PDR, with NPDR 217, and 255 with DWR. For promoter variant rs1051993 in AGER gene, allele and genotype distribution in PDR group differ from those in the group DWR (allele: P = 0.011; genotype: P = 0.01).
Compared with DWR, patients with PDR had a lower frequency of heterozygous genotype GT (9.8% for DWR, 1% for PDR, OR: 0.10, 95% CI: 0.01 to 0.72) and minor alleles T (4.9% for DWR, 0.5% for PDR, OR: 0.10, 95% CI: 0.01 to 0.75). In the multivariate model, the distribution of genotypes of rs1051993 in PDR group were significantly different from those in the group DWR (GT vs GG: OR: 0.07, 95% CI: 0.01 to 0.61, P <0.001). No association with DR SNP observed in other genotypes.
CONCLUSION The data showed a significant association of rs1051993 variant in the gene promoter AGER with PDR in the Chinese group with type 2 diabetes.
Association of candidate gene polymorphisms with diabetic retinopathy in Chinese patients with type 2 diabetes.
Sector retinitis pigmentosa: Report of ten cases and review of the literature.
To describe the genotypic and phenotypic ten patients with retinitis pigmentosa sector (RP). We also review previously reported mutations associated with RP sector and provide discussions about possible underlying pathophysiological mechanisms.
Patients underwent detailed ophthalmological examination, fundus photography, fundus autofluorescence (FAF) imaging, spectral-domain optical coherence tomography (SD-OCT), as well as visual field and electroretinographic testing. All patients underwent a genetic test to identify the molecular etiology of their disease.
result A total of ten patients studied. Among these patients, nine had mutations in RHO (c.677T> C; p.Leu226Pro (Novel), c.68C> A; p.Pro23His, c.808A> C; p.Ser270Arg, c.44A> G; p .Asn15Ser, and c.325G> A; p.Gly109Arg), and one patient had a mutation in RPGR (c.3092_3093delAG; p.Glu1031Glyfs * 47). All patients with missense mutations in RHO have visual acuities (VAS) better than 20/30 and showed sustained ellipsoid zone retinal foveal and topped structure.
Patients with deletion c.3092_3093delAG in RPGR have a VA of 20/60 oculus dexter (OD) and the 20/400 oculus sinister (OS), as well as significant foveal contour thinning and atrophy. All patients showed changes in pigment, or marked atrophy along the lower arcade, or both. This pattern of degeneration associated with visual disabilities and hyperFAF and superior hypo.
conclusion Sector RP is a rare form of RP in which only one or two quadrants of the retina display signs of clinical pathology. Most cases are caused by mutations in RHO. These data confirmed earlier reports phenotypic manifestations of RP sector. Low retinal quadrants may be more severely affected because of greater exposure to light.
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