Researchers from UK, Brazil and Italy identified the first family with a syndrome due to a mutation in APOO encoding MIC26, a component of the Mitochondrial Contact Site and Cristae Organizing System (MICOS). MICOS is considered the “mitoskeleton”, organizing the organelle cristae. The pathogenic change in MIC26 hits the hydrophobic region of the protein, compromising its processing and binding to the mitochondrial inner membrane, with consequent impairment of the cristae architecture and oxidative phosphorylation, an essential bioenergetic pathway carried out by the respiratory complexes within the mitochondrial cristae. (By Dr. Cristiane Benincá, https://jmg.bmj.com/content/early/2020/05/21/jmedgenet-2020-106861 )