In humans, missense mutations in RPL3L cause cardiomyopathy and lethal arrhythmia (Ganapathi et al., 2020; Das et al., 2022; Nannapaneni et al., 2022), and one of these studies showed no alteration in the patient’s mitochondrial genome due to the RPL3L missense mutation (Das et al., 2022). Here, RPL3L is linked to cardiomyopathy.