SCO1 patients suffer from hypertrophic cardiomyopathy, neonatal hepatopathy, and ketoacidotic comas, whereas mutations in COA6 cause fatal infantile cardioencephalomyopathy (Baertling et al., 2015; Banci et al., 2007; Calvo et al., 2012; Cobine et al., 2006; Stiburek et al., 2009; Valnot et al., 2000). Here, SCO1 is linked to hypertrophic cardiomyopathy.