Key proteins involved in mitochondrial fission, such as dynamin-related protein 1 (DRP1) and fission protein 1 (FIS1), are decreased in sarcopenia, impairing the isolation and removal of damaged mitochondria (Mao et al., 2021a; Mao et al., 2021b; Shi et al., 2023). The gene discussed is FIS1; the disease is sarcopenia.