AARS2 and lactic acidosis: In addition to mt-aaRS mutations that affect the pathology of the central nervous system, mt-AlaRS, mt-GlyRS, and mt-LysRS mutations are known to cause cardiomyopathies (Hei et al., 2019; Sommerville et al., 2019); mt-TyrRS mutations caused myopathy, lactic acidosis, and sideroblastic anemia (MLASA syndrome) (Shahni et al., 2013); and mt-SerRS mutations caused hyperuricemia, pulmonary hypertension, renal failure in infancy, and alkalosis (HUPRA syndrome) (Rivera et al., 2013).