OPA1 and glaucoma: The extent of the functional abnormalities correlated with the loss of normal RGC dendritic arborization that is thought to represent the first sign of RGC degeneration in glaucoma.61 A similar structural feature has also been found in the B6;C3-Opa1Q285STOP mouse model as a precursor of RGC degeneration.62 The architecture of dendritic arborization in patients with OPA1 mutations is not known, but our data support the idea that loss of dendritic arborization may be involved in the pathogenesis of DOA rather than just population loss.