TUBB3 and congenital fibrosis of the extraocular muscles: TUBB3 mutations can cause isolated or syndromic CFEOM3 (OMIM 600638) or malformations of cortical development (OMIM 614039).7 13 Two mutations (G71R and G98S) have been described to be associated with both malformations of cortical development and syndromic CFEOM.13 The variant presented in this study (E421D) represents the third variant where both phenotypes are seen.