Is IMP4 p.Arg274Cys (c.820C>T) pathogenic?

IMP4 p.Arg274Cys (c.820C>T) is classified Uncertain significance in IMP4 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-05-30). AlphaMissense: likely benign (0.2076); Very rare (popmax 0.00463%, eas).

How common is IMP4 p.Arg274Cys (c.820C>T) in the general population?

IMP4 p.Arg274Cys (c.820C>T) is very rare (popmax 0.00463%, eas) (gnomAD).

What do computational predictors say about IMP4 p.Arg274Cys (c.820C>T)?

AlphaMissense predicts likely benign (score 0.2076) — an in-silico prediction, not a clinical call.

IMP4 p.Arg274Cys

c.820C>T · rs867892713 · VCV2552809

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.2076 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00463%, eas)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.2076	likely benign
REVEL	0.29	benign-leaning
SaProt	LLR -8.11	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 4.8	phastCons 1
Regional constraint	o/e 0.93	unconstrained · MANE · 3,532 bp · p 0.15 · regional, not allelic
Overall
CADD	25.6	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

Grpmax group 0.00463% East Asian · 2/43,238 alleles

Filtering AF 0.000767% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000287%

Overall 0.000826% 13/1,573,874 alleles · very rare exomes 13/1,421,596 · genomes 0/152,278 · joint denominator

Ancestry group	Frequency	1 in
East Asiangrpmax	0.00463%	21,619
Remaining individualsnot grpmax-eligible	0.00328%	30,534
African / African-American	0.00134%	74,430
European (non-Finnish)	0.00069%	144,921

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: IMP4
Protein: p.Arg274Cys
Coding: c.820C>T
MANE Select: NM_033416
dbSNP: rs867892713
Type: single nucleotide variant
Location: chr2:130346412 (GRCh38)
Gene constraint: LOEUF 1.064 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 89.47 · 3 PDB
Residue 274: a β-strand

Full IMP4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

IMP4 p.Ala21Val Uncertain significance ★ ⚠ same type
IMP4 p.Ala282Thr Uncertain significance ★ ⚠ same type
IMP4 p.Arg126Gln Uncertain significance ★ ⚠ same type
IMP4 p.Arg170Trp Uncertain significance ★ ⚠ same type
IMP4 p.Arg194Cys Uncertain significance ★ ⚠ same type
IMP4 p.Arg198Gln Uncertain significance ★ ⚠ same type
IMP4 p.Arg204Gln Uncertain significance ★ ⚠ same type
IMP4 p.Arg216Gln Uncertain significance ★ ⚠ same type

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/imp4-p-arg274cys (accessed [today's date]).

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