COL4A4 and keratoconus: In terms of the dominant model, genotypes 422CC (OR=8.524) and 976GG (OR=30.645) in COL4A3 and 3979GG (OR=12.922), 4548AA (OR=1.993), and 4932CC (OR= 2.890) in COL4A4 are significantly related to KC patients (Table 5).