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An autosomal recessive disorder of cobalamin metabolism characterized by decreased levels of the coenzymes adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl). It is due to accumulation of free cobalamin in lysosomes, thus hindering its conversion to cofactors. Clinical features include developmental delay, stomatitis, glossitis, seizures and methylmalonic aciduria responsive to vitamin B12.




Cobalamin F disease
Methylcobalamin deficiency tape F
Methylmalonic acidemia and homocystinuria cblF type
Methylmalonic aciduria due to vitamin B12-release defect
Vitamin B12 lysosomal release defect
Vitamin B12 storage defect


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