Recessive COL25A1 mutations cause isolated congenital ptosis or exotropic Duane syndrome with synergistic divergence.

Congenital cranial dysinnervation disorders are phenotypes of incomitant strabismus and/or ptosis. Recessive mutations in COL25A1 are a recently reported cause, but the associated ophthalmic phenotypes have not been detailed. We highlight phenotypes of the 4 affected children from the 2 reported families: isolated congenital ptosis (one unilateral, one bilateral) and Duane syndrome (one unilateral, one bilateral) with synergistic divergence. Further study is needed to understand how frequently recessive COL25A1 mutations underlie these specific ocular phenotypes.