Notably, it was evident from our genotype to phenotype correlation analysis that dysfunction in one CYP1B1 allele is sufficient to cause disorders like POAG, as CYP1B1 mutations occur mostly in heterozygous condition in these diseases, but not in PCG where defects of both the alleles are required for precipitation of the disease phenotype. Here, CYP1B1 is linked to open-angle glaucoma.