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An autosomal recessive disorder of cobalamin metabolism characterized by decreased levels of the coenzymes adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl). Clinical features include developmental delay, hyotonia, mental retardation, seizures, megaloblastic anemia. Some patients manifest combined methylmalonic aciduria and homocystinuria (referred to as cblD original), some have only isolated homocystinuria (cblD variant 1), and others have only methylmalonic aciduria (cblD variant 2).




Homocystinuria cblD variant 1
Methylmalonic acidemia and homocystinuria cblD type
Methylmalonic aciduria and homocystinuria cblD-combined
Methylmalonic aciduria and homocystinuria cblD original
Methylmalonic aciduria cblD variant 2


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