A 50% reduction in ECHS1 causes cardiomyopathy phenotypes and lipid accumulation within liver and kidney.25,26 Cardiac impairments are not observed in all patient reports and are mostly limited to severe neonatal cases.3,4,15,32 Herein we focused on assessing neurological phenotypes as ECHS1D patients present with Leigh-like symptoms, however, future studies should assess cardiac function in ECHS1D mice. Here, ECHS1 is linked to cardiomyopathy.