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All Diseases > Cobalamin C disease (and other forms of methylmalonic acidemia and homocystinuria)
Cobalamin C disease (and other forms of methylmalonic acidemia and homocystinuria)
Alternative Names: cblC
Disease Category: Organic Acidemias
Methylmalonic acidemia with homocystinuria is an inherited disorder in which the body is unable to properly process certain nutrients from food including amino acids and lipids. People with this disorder have a combination of features from two separate conditions: methylmalonic acidemia and homocystinuria. When the condition begins early in life and is untreated, babies have difficulty gaining weight (failure to thrive), feeding difficulties, and a pale appearance. Babies may also have weak muscle tone (hypotonia) and seizures. Most babies and children with a severe form of this condition have a small head size (microcephaly), intellectual disability and developmental delay. Eye problems and a blood disorder called megaloblastic anemia can also occur. When the disorder begins in adolescence or adulthood and is untreated, the signs and symptoms usually include behavior and personality changes and cognitive problems (issues with learning, memory, perception etc). In some cases, abilities are lost, resulting in a decline of performance, memory and speech problems, dementia and lethargy. Methylmalonic acidemia with homocystinuria can be caused by genetic changes in one of several genes: MMACHC, MMADHC, LMBRD1, ABCD4, or HCFC1. Genetic changes in these genes account for the different types of the disorder, cblC, cblD, cblF, cblJ, and cblX, respectively. CblC disease is included on the recommended uniform newborn screening panel in the United States.
Research groups studying this disease
Organic Acidemias
Rare Organic Acidemias Research Consortium (ROAR)
Organic Acidemia Association
Our mission is to empower families and healthcare professionals with knowledge in organic acidemia metabolic disorders. We support early intervention through expanded newborn screening, solicit contributions and distribute funding that supports research toward improved treatment and eventual cures in the areas of organic acid disorders.