Four unrelated participants, also not meeting MDC, had large-angle exotropia, vertical gaze deficiency, and ptosis consistent with congenital fibrosis of the extraocular muscles type 3 (CFEOM3); 1 patient harbored a novel TUBB3 mutation, and 3 patients harbored previously reported de novo TUBB3 mutations.
Subjects with CFEOM3 frequently had asymmetrical blepharoptosis, limited vertical duction, variable ophthalmoplegia, exotropia, and paradoxical abduction in infraduction.