Table 3.

Functional classifications of currently non-treatable childhood dementia conditions

Aetiopathological classification	% of childhood dementia births
Inborn errors of metabolism (65.6% of births)
Lysosomal disorders (22.4% of births)
Lysosomal disorders of lipid metabolism and transport	10.1
Mucopolysaccharidoses	7.3
Glycoproteinosis	1.4
Other lysosomal diseases	3.6
Other disorders of lipid metabolism and transport	0.7
Disorders of amino acid and other organic acid metabolism	6.7
Vitamin-responsive inborn errors of metabolism	4.8
Disorders of mineral absorption and transport	1.0
Peroxisomal disease	9.5
Mitochondrial disorders	20.3
Other inborn errors of metabolism	0.1
Leukodystrophies not otherwise categorized	6.6
Neurodegeneration with brain iron accumulation	0.6
Diseases not otherwise categorised	27.3

Includes 69 conditions with data available, listed in Supplementary Table 1.