With our report we define the molecular basis of the previously described Leukoencephalopathy with Brainstem and Spinal cord Calcification, that we propose to call LBSC similarly to DARS and DARS2 related leukodystrophies, widening the spectrum of KARS related disorders, particularly in childhood onset disease suggestive for mitochondrial impairment. Here, KARS1 is linked to leukodystrophy.