R102G polymorphism of the complement component 3 gene in Malaysian subjects with neovascular age-related macular degeneration

Abstract

Background: Genetic and environmental factors are known to be risk factors in development of neovascular age-related macular degeneration (nAMD). Genetic factors such as polymorphisms in the complement component pathway genes might play a role in pathogenesis of nAMD and has been studied in various populations excluding Malaysia. Aim of the study: To determine the association of the R102G polymorphism of the complement component (C3) gene in nAMD subjects. Patients and methods: A total of 301 Malaysian subjects (149 case and 152 controls) were recruited and genotyped for the R102G (rs2230199) variant of the C3 gene. Genotyping was conducted using the PCR-RFLP method and association analysis was conducted using appropriate statistical tests. Results: From our findings, no significant association was observed in the allele distribution of C3 R102G between nAMD and controls (OR = 1.42, 95% CI = 0.77–2.62, P = 0.268). A further analysis that compared three genetic models (dominant, recessive and co-dominant) also recorded no significant difference (P > 0.05). These findings could be due to the low frequency of the GG variant in the case (4.7%) and control (1.3%) groups, compared to the normal variant CC, which is present in 91.3% of case and 92.8% of control alleles. Conclusion: The present study showed no evidence of association between C3 R102G polymorphism and nAMD in Malaysian subjects. Keywords: Age-related macular degeneration, Complement component 3, C3 gene, R102G gene polymorphism