hyper-IgM syndrome type 2
Findings
No curated finding names hyper-IgM syndrome type 2 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A hyper-IgM syndrome characterized by the absence of immunoglobulin class switch recombination, the lack of immunoglobulin somatic hypermutations, and lymph node hyperplasia caused by the presence of giant germinal centers.
Definition from the Mondo Disease Ontology (MONDO:0011528), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Childhood onset
HPO, annotations 2026-09-02
Features
11 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Decreased circulating IgA concentrationHPOHP:0002720
- 18 of 18 reported patients
- Decreased circulating IgG concentrationHPOHP:0004315
- 18 of 18 reported patients
- Recurrent bacterial infectionsHPOHP:0002718
- 18 of 18 reported patients
- Recurrent infection of the gastrointestinal tractHPOHP:0004798
- 18 of 18 reported patients
- Recurrent respiratory infectionsHPOHP:0002205
- 18 of 18 reported patients
- Increased circulating IgM concentrationHPOHP:0003496
- 15 of 18 reported patients
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- AICDAHGNC:13203
- Definitive · Ambry Genetics · Autosomal recessive · 2018
- Definitive · ClinGen · Autosomal recessive · 2024
- Definitive · ClinGen · Autosomal dominant · 2024
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2023
- Strong · PanelApp Australia · Autosomal recessive · 2025
Where it sits
Other names
5 names
Resolves to: hyper-IgM syndrome type 2
- Also called
- Activation-induced cytidine deaminase deficiencyAICDA hyper-IgM syndromeaid deficiencyHIGM2hyper-IgM syndrome caused by mutation in AICDA