IEMbase 0786: UNG-related hyper-IgM type 5
Scope
| Field | Value |
|---|---|
| IEMbase ID | 786 |
| Nosology | 16.3.06.01 |
| Nosology code | IEM0006 |
| Gene | UNG |
| External IDs | OMIM:608106; ORPHA:101092 |
| Generated mapping | UNMAPPED |
| Candidate DisMech targets | No exact local target; reject IKBKG_Ectodermal_Dysplasia_with_Immunodeficiency.yaml candidate |
| Review date | 2026-07-11 |
IEMbase phenotype signal
IEMbase labels this autosomal recessive record as UNG-related uracil-DNA glycosylase deficiency, with alternate name immunodeficiency with hyper-IgM type 5 and abbreviation HIGM5. The phenotype signal resembles AICDA/HIGM2: recurrent bacterial infections, lymphoid hyperplasia, giant germinal centers in lymph nodes, impaired immunoglobulin class-switch recombination, low IgG, low IgA, low IgE, normal B-cell counts, and normal or increased IgM.
DisMech phenotype coverage
No exact DisMech target was found. Local entries do include hyper-IgM-like patterns in other immunodeficiencies, including IKBKG/NEMO-related disease, but those have distinct genes and mechanisms. They should not be used as coverage for UNG deficiency.
Concordance and completeness
Judgement: true local gap.
The generated IKBKG/IMD33 candidate is a phenotypic neighbor because both can show class-switch or hyper-IgM-like humoral abnormalities. It is not an exact match for uracil-DNA glycosylase deficiency, and the current local knowledge base lacks UNG/HIGM5-specific coverage.
Curation actions
- Keep IEMbase 0786 unmapped.
- Reject IKBKG-related ectodermal dysplasia with immunodeficiency and other hyper-IgM-like neighbors as exact coverage.
- Future curation should preserve the UNG-specific DNA-repair/class-switch mechanism and the normal-B-cell, low-IgG/IgA/IgE, normal-to-high-IgM profile.