MMADHC
2q23 MIM.609831 HGNC:25221 Entrez:27249 ENSG00000168288
This gene encodes a mitochondrial protein that is involved in an early step of vitamin B12 metabolism. Vitamin B12 (cobalamin) is essential for normal development and survival in humans.
Pathology
Mutations in MMADHC gene cause cobalamine defiency type C (or methylmalonic aciduria and homocystinuria type cblD - MMADHC) (MIM.277400).
The cobalamine defiency type C is a disorder of cobalamin metabolism that is characterized by decreased levels of the coenzymes adenosylcobalamin and methylcobalamin. Pseudogenes have been identified on chromosomes 11 and X.
The cblC type of combined methylmalonic aciduria and homocystinuria is caused by mutation in the MMACHC gene (MIM.609831) on chromosome 1p34.1.