Aggregation‐prone proteins such as the huntingtin protein in Huntington's disease, α‐synuclein in Parkinson's disease, or mutant AD proteins in Alzheimer's disease abnormally interact with Drp1, leading to increased activity of Drp1, access of mitochondrial fragmentation and damage in neurons. Here, DNM1L is linked to early-onset autosomal dominant Alzheimer disease.