OPA1 and neurodegenerative disease: Abnormalities in the function of molecules related to mitochondrial dynamics have been shown to play an important role in certain diseases, for example, OPA1 and MFN2 mutations are causative factors in two neurodegenerative diseases (Amati-Bonneau et al. 2008), and muscle defects associated with neuromyelination have also been found in mice carrying OPA1 mutations (Alavi et al. 2009).