WARS2 and cardiac hypertrophy: In murine studies, heart-specific loss of Dars2 causes cardiac hypertrophy.35 Chemical random mutagenesis in WARS2V117L causes sensorineural hearing loss and HCM in mice.36 However, studies of DARS2 and WARS2 showed no direct clinical evidence for humans.11,13 Here, we demonstrated that another member of mtARS, FARS2, is a novel pathogenic gene in HCM.