APOE and open-angle glaucoma: We compared the APOE genotypes containing at least one ε2 allele (ε2/ε2, ε2/ε3, ε2/ε4: T in codon 158) and the APOE genotypes without an ε2 allele (ε3/ε3, ε4/ε4, ε3/ε4: C in codon 158) between the patients with POAG, XFS, and XFG and the control subjects.