MMADHC Human
Description
Product Specs
Product Science Overview
The cblD type of methylmalonic aciduria with homocystinuria is caused by mutations in the MMADHC gene located on chromosome 2q23.2 . This gene is responsible for encoding a protein that is involved in the conversion of vitamin B12 into its active forms, adenosylcobalamin and methylcobalamin. These active forms are essential cofactors for the enzymes methylmalonyl-CoA mutase and methionine synthase, respectively .
Due to the mutations in the MMADHC gene, individuals with this disorder have reduced levels of adenosylcobalamin and methylcobalamin. This leads to a decrease in the activity of methylmalonyl-CoA mutase and methionine synthase, resulting in the accumulation of methylmalonic acid and homocysteine in the body . The buildup of these substances can cause a wide range of symptoms and complications.
The clinical presentation of methylmalonic aciduria cblD type with homocystinuria can vary widely, but common features include :
- Developmental delay
- Intellectual disability
- Seizures
- Hypotonia (reduced muscle tone)
- Megaloblastic anemia (a type of anemia characterized by large, abnormal red blood cells)
- Failure to thrive
- Feeding difficulties
- Behavioral problems
- Movement and gait abnormalities
In some cases, individuals may also experience neurological deterioration, retinal degeneration, and other severe brain abnormalities .
Diagnosis of methylmalonic aciduria cblD type with homocystinuria typically involves measuring the levels of organic acids and amino acids in the blood and urine. Elevated levels of methylmalonic acid and homocysteine are indicative of the disorder . Genetic testing can confirm the diagnosis by identifying mutations in the MMADHC gene .
Management of this disorder often involves dietary modifications to reduce the intake of certain amino acids and the administration of vitamin B12 supplements in the form of hydroxocobalamin or cyanocobalamin . Other treatments may include medications to lower homocysteine levels and supportive therapies to address specific symptoms and complications .
