Gene networks determine predisposition to AMD.

PURPOSE:AMD genetic studies have revealed various genetic loci as causal to AMD pathology. We have described the genetic complexity of Indian AMD by describing the interaction of genotypes and subsequent changes in protein expression under the influence of environmental factors. This can be utilized to enhance the diagnostic and therapeutic efficacy in AMD patients. DESIGN:Genotype association was studied in 464 participants (AMD =277 & controls = 187) for eight genetic variants and their corresponding protein expression METHODS: SNP analysis and protein expression analysis was carried out in AMD and controls in tandem with longitudinal assessment of protein levels during the course of AMD pathology. ANCOVA and contrast analysis were used to examine the genotypic interactions and corresponding alterations in protein levels. In order to identify the important genetic variants Logistic Regression (LR) modeling was carried out and to authenticate the model Area under the Receiver Operating Characteristic curve (AUROC) were also computed. RESULTS:We have found genetic variants of rs5749482 (TIMP-3), rs11200638 (HTRA1), rs769449 (APOE) and rs6795735 (ADAMTS9) to be associated with AMD, concomitant with significant alterations of studied proteins levels. Analysis also revealed that the genetic interaction between APOE-HTRA1 genotypes and changes in LIPC levels (>6 pg/ug) by one unit change in SNP, play a crucial role in AMD. LR model suggested that the seven factors (including both genetic and environmental) can be utilized to predict the AMD cases with 88% efficacy and 95.6% AUROC. CONCLUSION:Results suggest that diagnostic and therapeutic strategy for Indian AMD must include estimation of genetic interaction and concomitant changes in expression levels of proteins under influence of environmental factors.