Is AICDA p.Arg178His (c.533G>A) pathogenic?

AICDA p.Arg178His (c.533G>A) is classified Uncertain significance in AICDA (ClinVar, Single submitter, 1 submitter; last evaluated 2024-12-19). AlphaMissense: likely benign (0.2531); Absent from gnomAD v4.1; Associated with hyper-IgM syndrome type 2.

What condition is associated with AICDA p.Arg178His (c.533G>A)?

AICDA p.Arg178His (c.533G>A) is associated with hyper-IgM syndrome type 2 (ClinVar).

How common is AICDA p.Arg178His (c.533G>A) in the general population?

AICDA p.Arg178His (c.533G>A) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about AICDA p.Arg178His (c.533G>A)?

AlphaMissense predicts likely benign (score 0.2531) — an in-silico prediction, not a clinical call.

AICDA p.Arg178His

c.533G>A · VCV3685682

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.2531 · ACMG-weighted

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,612,412)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

hyper-IgM syndrome type 2

Computational evidence

Protein change
AlphaMissense	0.2531	likely benign
REVEL	0.193	benign-leaning
SaProt	LLR -7.15	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.6	GERP -0.22, phastCons 1
Regional constraint	o/e 0.86	unconstrained · MANE · 8,480 bp · p 0.018 · regional, not allelic
Overall
CADD	27.0	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

No allele count reported in gnomAD v4.1 (AN 1,612,412). This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: AICDA
Protein: p.Arg178His
Coding: c.533G>A
MANE Select: NM_020661
Type: single nucleotide variant
Location: chr12:8604817 (GRCh38)
Gene constraint: LOEUF 1.144 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 88.43 · 5 PDB
Residue 178: an α-helix

Full AICDA gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

hyper-IgM syndrome type 2 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

AICDA p.Arg178Pro Uncertain significance ★★ ⚠ same residue
AICDA p.Arg112Cys Pathogenic ★★ same condition
AICDA p.Arg190Ter Pathogenic/Likely pathogenic ★★ same condition
AICDA p.Arg24Trp Pathogenic ★★ same condition
AICDA p.Arg92Ter Pathogenic/Likely pathogenic ★★ same condition
AICDA p.Arg99Ter Pathogenic/Likely pathogenic ★★ same condition
AICDA p.Cys147Ter Pathogenic ★★ same condition
AICDA p.Cys87Arg Pathogenic/Likely pathogenic ★★ ⚠ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/aicda-p-arg178his (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown