According to current research, the most affected tissues from the OPA1 mutation and depletion are the retina and brain, leading to a variety of neurodegenerative diseases, such as DOA, chronic progressive external ophthalmoplegia (CPEO), PD, and dementia (Ferré et al., 2005; Olichon et al., 2007; Zanna et al., 2008; Williams et al., 2012; Kushnareva et al., 2013; Carelli et al., 2015a; Santarelli et al., 2015; Zorzano and Claret, 2015). Here, OPA1 is linked to External ophthalmoplegia.