AARS2 and Hereditary diffuse leukoencephalopathy with axonal spheroids and pigmented glia: Numerous publications have documented significant phenotypic variability caused by defects in mtARS genes.6, 7 Patients harboring biallelic mutation in AARS2, for example, may present with intrauterine or perinatal cardiomyopathy,20 adolescent onset ovario leukodystrophy21 or late‐onset neurodegeneration in patients with hereditary diffuse leukoencephalopathy with spheroids (HDLS).22 The explanation for the broad range of manifestations is unclear.