SIX6 and pathologic nystagmus: Gallardo et al. [14] identified a heterozygous c.493A>G (p.T165A) variation in SIX6 in a patient with bilateral microphthalmia, cataract, and nystagmus from among a series of 73 patients with syndromic or nonsyndromic sporadic clinical anophthalmia and microphthalmia.