The co-existence of the heterologous minor alleles (OR = 0.32, 95% CI: 0.14–0.71; p = 0.0038) or genotypes (OR = 0.24; 95% CI: 0.1–0.58; p = 0.0018) of IL12B were associated with a significant reduction in the risk of keratitis. Here, IL12B is linked to keratitis.