Authors: Li Tao, Xu Yi, Chen Jianhua, Xu Xian, Xu Xun, He Xiangui, Lu Lina, Zhu Jianfeng, Shi Yongyong, Zou Haidong
To investigate whether the presence of complement factor H(CFH) gene polymorphisms is associated with unexplained mild visual loss (UMVL) in type 2 diabetes mellitus patients.
A case control study was adopted.The participants included two groups from a previous population-based epidemiology study on type 2 diabetes mellitus patients in the Beixinjing community, Shanghai: UMVL was defined by a best corrected visual acuity(BCVA)<20/25 and≥20/63 in both eyes, with no eye diseases causing visual impairment, such as corneal diseases, cataract, age-related macular degeneration, glaucoma, optic nerve atrophy, diabetic retinopathy, etc.Genomic DNA was isolated from the peripheral venous blood of all the participants and then loaded onto Fluidigm Digital Arrays.Four CFH gene single nucleotide polymorphisms (SNPs)(rs800292, rs1061170, rs529825, rs1410996, rs203674) were assessed with the SPSS 13.0 and HAPLoVIEW 4.0 software to test the statistical association of CFH polymorphisms with UMVL.The study protocol was approved by the Ethics Committee of Shanghai General Hospital, Shanghai Jiaotong University(No.2013KY023). All the procedures were conducted according to the tenets of the Declaration of Helsinki.Written informed consent was obtained from each subject prior to entering the study cohort.
Total of 135 residents with UMVL and 133 with normal vision(BCVA≥20/25 in both eyes) were enrolled.The UMVL group matched the control group in terms of gender, age, onset age, and duration of diabetes mellitus, hemoglobin A1c levels, and body mass index(all at P>0.05). The four SNPs(rs800292, rs1061170, rs529825, rs1410996) except rs203674 tested in the UMVL and control groups were qualified by the Hardy-Weinberg equilibrium (P>0.05). There were no differences in SNPs and genotypes between the two groups in the four loci of the CFH gene.The P value of allele frequencies of rs529825, rs800292, rs1410996 and rs1061170 were 0.79, 0.25, 0.69 and 0.77, respectively, and the P value of genotype frequencies were 0.61, 0.69, 0.87 and 0.43, respectively.
There is no correlation between CFH gene polymorphism and UMVL in type 2 diabetic patients.