They involve the cerebral WM in five recessive ataxias including cerebrotendinous xanthomatosis (CTX) (OMIM 213700), 2-hydroxic glutaric aciduria (OMIM 236792), hypomyelinating leukodystrophy type 2 (HLD2) (OMIM 608804), leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL)(OMIM 611105), and SCAR4/SCA24 (OMIM 607317). This evidence concerns the gene VPS13D and hypomyelinating leukodystrophy 2.