Abstract
Purpose: :
To examine the common single-nucleotide polymorphisms in complement factor H (CFH), LOC387715, and HTRA1 genes as potential risk factors for exudative age-related macular degeneration (AMD) in the mainland Chinese.
Methods: :
A cohort of 121 unrelated patients with exudative AMD and 132 age- and sex-matched control subjects, all unrelated ethnic Chinese from Northern China, enrolled in this study. Genomic DNA was extracted from blood leukocytes. Genotyping for CFH Y402H, LOC387715 A69S, and HTRA1 -625G>A polymorphisms was performed by analyzing amplified genomic fragments using a method of polymerase chain reaction (PCR) followed by allele specific restriction enzyme digestion and direct sequencing.
Results: :
Frequencies of the CFH variant Y402H in AMD patients and control subjects were 10.3% and 7.6%, respectively, and were not associated with exudative AMD in our study population (p = 0.353). Significant associations were detected for exudative AMD in mainland Chinese with LOC387715 variant A69S and the HTRA1 promoter polymorphism -625G>A. Homozygote for the LOC387715 A69S polymorphism was associated with an odds ratio (OR) of 5.45 (95% confidence interval, 2.59-11.49) for exudative AMD. An odds ratio of 7.90 (95% confidence interval, 3.61-17.26) for exudative AMD was found among carriers of the homozygous HTRA1 -625G>A genotype. Individuals with both homozygous LOC387715 A69S and homozygous HTRA1 -625G>A polymorphism were associated with an odds ration of 7.94 (95% confidence interval, 3.49-18.04).
Conclusions: :
Our data suggest that the LOC387715 and HTRA1 polymorphisms, but not the CFH Y402H, are associated with a higher risk of exudative AMD in the mainland Chinese. The low frequency of CFH Y402H variant was further confirmed among the Chinese population.
Keywords: age-related macular degeneration • genetics • gene screening