VWM is caused by homozygote or compound heterozygote pathogenic variants in one of five genes (EIF2B1, EIF2B2, EIF2B3, EIF2B4, and EIF2B5), which encode the five subunits of the eukaryotic translation initiation factor 2B holocomplex (EIF2B) (5). The gene discussed is EIF2B4; the disease is leukoencephalopathy with vanishing white matter.