Abstract
Purpose: :
Glaucoma, the second leading cause of irreversible blindness in the world, comprises a heterogeneous group of optic neuropathies with a complex genetic basis. A group of SNPs on chromosome 2p previously have been reported to be associated with primary open-angle glaucoma (POAG) in Afro-Caribbean and Afro-American populations This study investigates the association of these SNPs with POAG in a Southern Indian population.
Methods: :
Case-control analysis was performed using unrelated affected individuals (220 POAG cases) and age matched unaffected controls (220 controls). Five SNPs (rs1533428, rs12994401, rs10202118, rs11125375 and rs11889995) on chromosome 2p were evaluated in these two groups and genotyped using a Taq Man SNP genotyping assay. Hardy Weinberg equilibrium was demonstrated for all markers and the distributions of allele and genotype frequencies were calculated by the chi-square test, the trend test, and Fisher’s exact test under various inheritance models as implemented in the Golden Helix SVS program package.
Results: :
Among the five SNPs screened, two SNPs showed significant association in Indian POAG patients. The SNP rs10202118, showed a p = 0.027 for the basic allelic test, p = 0.004 for the genotypic chi square test, and p = 0.00095 for the recessive model, which remained significant after correction for multiple testing. rs11125375 Showed a suggestive chi square p = 0.025 for the recessive model. The associated SNPs form a common disease haplotype. The remaining three SNPs did not show significant association in this study population.
Conclusions: :
This is the first study to demonstrate the association of SNPs on chromosome 2p in patients with POAG in the Indian population. These results confirm and extend the previously reported association of SNPs on chromosome 2p with POAG in African-derived populations.
Keywords: genetics • gene screening • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology