| Namespace | disease_ontology | Obsolete | false |
| description | A combined T cell and B cell immunodeficiency that is a X-linked immunodeficiency with hyperimmunoglobulin M (XHIM) affecting isotype switching and is caused by the absence of CD40 ligand which is normally expressed on activated CD4+ T cells. Individuals with this mutation are unable to switch from IgM to IgG, IgA and IgE. |
