PAX6 and microphthalmia: In fact, Tzoulaki et al. reported that missense mutations in PAX6 are responsible for nearly 70% of non-aniridia eye disorders that were registered in the database (Figure 3C) [78], like microphthalmia, optic nerve anomalies, coloboma, isolated foveal hypoplasia, and anterior segment dysgenesis (discussed in Section 6.3).