The importance of eIF2B function within the cell is highlighted by the fact that loss of function mutations in any of the five subunits of eIF2B lead to the fatal neurological disorder, leukoencephalopathy with vanishing white matter (VWMD), also known as childhood ataxia with central nervous system hypomyelination (CACH) [7]. This evidence concerns the gene EIF2B5 and Leukoencephalopathy.