Abstract
Purpose:
To conduct a meta-analysis of the association of LOXL1 single nucleotide polymorphisms with pseudoexfoliation (PEX) in populations of different race/ethnicity.
Methods:
Association studies were retrieved from PubMed, Embase and Web of Knowledge, using 10 July 2013 as cut-off date. Eligibility criteria were applied and data were extracted by two independent investigators. Allelic distributions of rs3825942 (G153D), rs1048661 (R141L) and rs2165241 were compared between subjects with PEX (with and without glaucoma) and controls. Random effects model was used to synthesize the data. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from the allelic model. Heterogeneity between studies was assessed using the Q-test and I2 statistic.
Results:
We identified 70 potentially relevant studies. Results are presented for populations in which at least two genetic association studies have been conducted. The G allele of rs3825942 was associated with increased risk of PEX in Caucasians (14 studies, OR=8.12, 95%CI:5.00-13.18; I2=76.9%, p<0.001), Japanese (5 studies, OR=17.57, 95%CI:9.15-33.74; I2=0%, p=0.590), Koreans (2 studies, OR=8.79 95%CI:3.49-22.15; I2=0%, p=0.543) and Chinese (2 studies, OR=14.15 95%CI:2.77-72.38; I2=0%, p=0.668). The G allele of rs1048661 was also associated with increased risk of PEX in Caucasians (13 studies, OR=2.21 95%CI:2.00-2.45; I2=0%, p=0.683), but the association was reversed in Japanese (5 studies, OR=0.04, 95%CI:0.02-0.06; I2=39.7%, p=0.156) and in Koreans (2 studies, OR=0.10 95%CI:0.05-0.22; I2=49.5%, p=0.159). In Chinese the association with rs1048661 was not statistically significant (OR=0.43, 95%CI:0.04-4.31; I2=97.1%, p<0.001). Similarly, the T allele of rs2165241 was associated with increased risk of PEX in Caucasians (9 studies, OR=3.50 95%CI:3.16-3.88; I2=0%, p=0.869), but the association was reversed in Japanese (3 studies, OR=0.13 95%CI:0.06-0.31; I2=32.9%, p=0.225) and in Koreans (2 studies, OR=0.15 95%CI:0.06-0.38; I2=0%, p=0.778).
Conclusions:
The G allele of rs3825942 confers risk of PEX in Caucasian, Japanese, Korean and Chinese populations. The G allele of rs1048661 and the T allele of rs2165241 are associated with increased risk of PEX in Caucasians, but these associations seem to be reversed in Japanese and in Koreans.