| Disease ID | Source | Name | Description |
| 277410 | OMIM | Methylmalonic aciduria and homocystinuria, cblD type (MAHCD) | 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). The disease is caused by variants affecting the gene represented in this entry. |