Evaluation of BLID and LOC399959 as candidate genes for high myopia in the Chinese Han population

While rs577948 may be associated with high myopia in Japanese subjects, it and the other tSNPs near the BLID and LOC399959 genes are not susceptibility loci for high myopia in the Chinese Han population. Thus, associations of SNPs with high myopia as determined by Genome-Wide Association Study (GWAS) may be restricted to certain ethnic or genetically distinct populations. Without systematic replication in other populations, the results of GWAS associations should be interpreted with great caution.

High myopia subjects (n=476) had a spherical refractive error of less than -6.00 D in at least one eye and/or an axial length greater than 26 mm. Genomic DNA was extracted and genotyped from peripheral blood leukocytes of high myopes and controls (n=275). Using a case-control association study of candidate regions, linkage disequilibrium blocks for 19 tag SNPs (tSNPs), including rs577948, harbored within and surrounding the BLID and LOC399959 genes were analyzed on a MassArray platform using iPlex chemistry. Each of the tSNPs had an r(2)>0.8 and minor allele frequency >10% in the Chinese Han population. Haplotype association analysis was performed on Haploview 4.1 using Chi-square (χ(2)) tests.

BH3-like motif containing, cell death inducer (BLID) and LOC399959 are two genes associated with the single nucleotide polymorphism (SNP) rs577948, which is a susceptibility locus for high myopia in Japanese subjects. The purpose of this study was to determine if BLID and LOC399959 are associated with high myopia in Chinese Han subjects.

None of the 19 tSNPs were statistically associated with high myopia. Conclusions: While rs577948 may be associated with high myopia in Japanese subjects, it and the other tSNPs near the BLID and LOC399959 genes are not susceptibility loci for high myopia in the Chinese Han population. Thus, associations of SNPs with high myopia as determined by Genome-Wide Association Study (GWAS) may be restricted to certain ethnic or genetically distinct populations. Without systematic replication in other populations, the results of GWAS associations should be interpreted with great caution.