Enzymes that are targeted into mitochondria could affect mt-tRF biogenesis, like RNase ZL/ELAC2, which has been identified as a hotspot for mutations linked with mitochondrial diseases, such as hypertrophic cardiomyopathy but also with prostate cancer (Siira et al., 2018; Saoura et al., 2019). The gene discussed is ELAC2; the disease is hypertrophic cardiomyopathy.