Abstract
Purpose: :
Age-related degeneration (AMD) is the leading cause of vision loss and blindness among older individuals. Although the etiology of AMD is not clearly understood, AMD has a strong genetic predisposition. Complement Factor I (CFI, MIM 217030), which is a a serine proteinase in the complement pathway responsible for cleaving and inactivating the activities of C4b and C3b, is encoded at 4q25. To determine the possibility of CFI gene as potential susceptibility candidate gene for Korean patients with AMD, we investigated the association of the CFI variants in unrelated Korean patients with AMD
Methods: :
Total genomic DNAs were extracted from buccal swab samples of 120 unrelated patients with exudative AMD visited the the Eye Center of Seoul St. Mary’s Hospital. Genotyping of rs10033900, rs13117504 and rs9998151 of the CFI gene was performed using polymerase chain reaction - BsaJI, Fnu4HI and NlaIII RFLP and direct sequencing, respectively. Age matched 230 control individuals from Korea Centers for Disease Control and Prevention with no history of AMD were also enrolled
Results: :
In this study, we investigated 3 SNPs for CFI gene ; rs10033900, rs13117504 and rs9998151. Among them, rs13117504 was significantly associated with an increased risk of AMD. The frequencies of the *G/*G, *G/*C and *C/*C genotypes were 23.6%, 61.8% and 14.6% in AMD patients and were 17.6%, 46.7% and 35.7% in control subejcts, respectively. The *G/*G (p =0.051, O.R. = 1.45, 95% CI: 0.825<<2.534) and *G/*C genotypes (p =0.01, O.R. = 1.91, 95% CI: 1.175<<3.109) for rs13117504 of CFI was more prevalent in patients with AMD than among control subjects. Whereas *C/*C genotype in AMD patients was significantly decreased compared with the control subjects (p=0.001, O.R. = 0.309, 95% CI: 0.173<<0.551). AMD patients had significantly higher G allele frequency than controls (p=0.001, O.R. = 1.726, 95% CI 1.246<<2.392). rs10033900 and rs9998151 showed no significant genotype frequency differences between AMD patients and control subjects. The genotype distributions of all polymorphisms of CFI among the control subjects and the affected individuals were in Hardy-Weinberg equilibrium
Conclusions: :
In this study, Korean AMD patients showed significantly difference in rs13117504 of CFI. Therefore, it is suggested that rs13117504 in 3’ region of CFI seems to be associated with AMD predisposition in a Korean
Keywords: age-related macular degeneration • genetics • gene screening