NYX and pathologic nystagmus: In our patients, the patients carrying NYX mutation of c.371_377del GCTACCT (p.Y125TfsX138) had reduced visual acuity ≤0.4, myopia of the spherical equivalent range from −3.0D to −10.0D, dissociated vertical deviation, extropia and nystagmus, whereas the patient carrying NYX mutation of c.214A>C (p.N72H) had only high myopia of −10.0D and intermittent extropia.