Although Mfn1 and Mfn2 have similar functions and are even functionally complementary in specific situations, only mutations in Mfn2 cause significant physiological changes leading to neurodegenerative diseases, such as type 2A peroneal muscular atrophy neuropathy (Sloat et al., 2019). The gene discussed is MFN2; the disease is neurodegenerative disease.