Type of LD   % of Truncal hypotonia   % of Eye abnormality % of Abnormal BERA test    % of other characteristics Peliazeus-Merzbacher disease* high† high high vary†† Mitchap 60 disease‡ high high high vary Metachromatic-leukodystrophy high high high vary Refsum disease high high high vary Zellweger disease high high high vary Alexander disease high high high vary Canavan disease high high high vary Krabbe' disease high high high vary Vanishing white matter high high high vary Aircadi-Goutie'res syndrome‡ high high high vary

Table 2: The prevalence of the triad of characteristics in the known types of leukodystrophy (LD). X-linked LD. † A major presenting symptom. †† less or slightly high frequent presenting symptom or sign such as irritability, epilepsy etc. ‡ Recently detected autosomal recessive LD, from 2009.