Association of HERPUD1 genetic variant rs2217332 with age-related macular degeneration and polypoidal choroidal vasculopathy in an Indian cohort.

PURPOSE: Age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) are sister diseases and have several similar clinical features and still have few genetic differences. The association of HERPUD1 (homocysteine inducible ER protein with ubiquitin like domain 1) gene variant rs2217332 with PCV is known; however, such association with AMD has not been reported in the Indian population. We analyzed the association of rs2217332 with PCV and AMD to identify the preferential association of this variant with these diseases. METHODS: This is a population-based case-control study consisting of 422 patients (129 AMD cases; 101 PCV cases, 192 healthy controls) recruited from the vitreoretinal clinic Sankara Nethralaya. The sample size for the study was calculated using appropriate power calculation methods. Genotype was determined using PCR-based Sanger sequencing. The SPSS V23.0 statistical package tool was used to calculate chi-square and ROC to determine the association of rs2217332 with control, AMD, and PCV. RESULTS: Here, we report for the first time the association of this genetic variant (rs2217332) with AMD and PCV in the Indian population. The case-control study shows a significant association of this SNP with PCV (P value = 0.002); however, this variant is not significantly associated with AMD (P value = 0.602). Comparison between AMD (as control) and PCV (as case) also showed significant association of the SNP with PCV (P value = 0.02). Minor allele A conferred to increase the risk of PCV. CONCLUSIONS: The study concludes that the genetic variant rs2217332 in HERPUD1 gene is highly significantly associated with PCV and not with AMD in Indian populations.

Development of an automated system for the detection of genotype in polypoidal choroidal vasculopathy using retinal image phenotype.

BACKGROUND AND OBJECTIVES: Polypoidal choroidal vasculopathy (PCV) is a retinal disorder characterized by the presence of aneurismal polypoidal lesions in the choroidal vasculature. A single nucleotide polymorphism (SNP) is a common genetic variant which may be associated with the disease. This study is to investigate the association of HERPUD1 (rs2217332) gene with PCV in the Indian population and develop an automated system for genotype and phenotype correlation using fundus images and machine learning methods. METHODS: A cohort of 54 PCV patients and 120 control subjects were recruited for the study. Genotyping of SNP (HERPUD1, rs2217332) was performed by following polymerase chain reaction and direct sequencing method. Statistical association of SNP to PCV was determined using chi-square analysis. The acquired GG and AG images were preprocessed using an adaptive histogram. 19 and 18 texture features were extracted from the images in the PCV naïve cases and PCV patients on treatment, respectively. Student's independent t-test was then employed for the selection of significant features, which were input to the ensemble tree for automated classification. Leave-one-out validation was used to evaluate the system. RESULTS: HERPUD1 rs2217332 SNP is significantly associated in PCV patients compared to control (P = 0.0296, odds ratio [OD] = 2.297, 95% confidence interval [CI] = 1.087-4.856) in the Indian population. High F1 and precision values of 85.71%, 86.84% and 85.71%, 93.75% were achieved in the pre and post- treatment phases, respectively. CONCLUSION: Our results suggest that the HERPUD1 polymorphism is associated in PCV patients. Based on our analysis, it may be possible to predict the genotype and disease status of PCV patients using fundus images in assistance with a machine learning algorithm.

Fabrication of electrochemical biosensor with vanadium pentoxide nano-interface for the detection of methylglyoxal in rice.

Increased consumption of raw and par-boiled rice results in the formation of methylglyoxal (MG) at higher concentration and leads to complications in diabetic patients. Highly sensitive electrochemical biosensor was developed using glutathione (GSH) as a co-factor with vanadium pentoxide (V2O5) as a nano-interface for MG detection in rice samples. The Pt/V2O5/GSH/Chitosan bioelectrode displayed two well-defined redox peaks in its cyclic voltammograms for MG reduction. This occurred as two electron transfer process where MG gained two electrons from oxidized glutathione disulfide and formed hemithioacetal. The current density response of the fabricated bioelectrode was linear towards MG in the concentration range of 0.1-100 µM with the correlation coefficient of 0.99, sensitivity of 1130.86 µA cm-2 µM-1, limit of detection of 2 nM and response time of less than 18 s. The developed bioelectrode was used for the detection of MG in raw and par-boiled rice samples.