C3 gene polymorphism R102G in a Greek population with age‐related macular degeneration

Purpose To elucidate whether C3 R102G polymorphism is a major genetic determinant of AMD in a Greek population as well as to evaluate its prognostic importance for progression to advanced AMD Methods A clinic‐based case‐control association study was conducted, comprising 98 Greek patients with early‐ and advanced‐stage AMD and 125 independent controls of Caucasian origin. All participants underwent a complete ophthalmic examination, fluorescein angiography and OCT. Information on cigarette smoking, hypertension and family history was obtained by interview at baseline. Moreover, they were genotyped for C3 R102G polymorphism, by using ARMS‐PCR. Results The frequency of the C3 R102G allele was significantly higher in AMD patients in comparison with controls while the odds ratio (OR) for AMD was 1,46 (CI 95% = 0,82‐2,59). Statistical comparison between early and advanced AMD patients, on the basis of C3 genotypic frequencies, revealed that the C3 R102G allele was more prevalent in advanced AMD patients (P<0,05, OR=2,62). Moreover, both GG and CG genotypes were found to be more prevalent in patients with neovascular AMD (ORs = 3,95 and 2,51, respectively) when compared with non‐exudative AMD patients. Concerning family history, it is significantly higher among patients with GG genotype when compared to CG and CC genotypes. On the contrary, C allele was associated with hypertension and smoking in AMD patients when compared to G allele. Conclusion The replication of the reported associations of C3 R102G polymorphism with AMD suggest that the 102G allele could serve as a genetic marker for the development of AMD and the progression of the disease to the advanced clinical stage in the Greek population.