MFN2 and frontotemporal dementia: Moreover, a biological interaction between MFN2 and TDP-43, the main protein involved in amyotrophic lateral sclerosis pathogenesis, has been described in an amyotrophic lateral sclerosis mouse model.23 Here, we reported a retrospective study on a large Italian cohort of amyotrophic lateral sclerosis patients aimed at investigating the presence of MFN2 variants in patients with amyotrophic lateral sclerosis/frontotemporal dementia.