Is CKAP2 p.Arg281Trp (c.841C>T) pathogenic?

CKAP2 p.Arg281Trp (c.841C>T) is classified Uncertain significance in CKAP2 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-12-15). AlphaMissense: likely benign (0.0791); Very rare (popmax 0.00667%, amr).

How common is CKAP2 p.Arg281Trp (c.841C>T) in the general population?

CKAP2 p.Arg281Trp (c.841C>T) is very rare (popmax 0.00667%, amr) (gnomAD).

What do computational predictors say about CKAP2 p.Arg281Trp (c.841C>T)?

AlphaMissense predicts likely benign (score 0.0791) — an in-silico prediction, not a clinical call.

CKAP2 p.Arg281Trp

c.841C>T · rs200602489 · VCV3145201

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0791 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00667%, amr)

Missense predictors

1/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.0791	likely benign
REVEL	0.011	strongly benign-leaning
SaProt	LLR -10.68	damaging
⇒ SaProt calls this damaging; AlphaMissense and REVEL do not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -0.11	GERP -1.3
Regional constraint	o/e 1.06	unconstrained · MANE · 6,978 bp · p 0.17 · regional, not allelic
Overall
CADD	16.56	PHRED · no single calibrated threshold — expert panels disagree

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

⚠ Isoform check: AlphaMissense numbered on a different transcript (AM R282W vs ClinVar R281W) — verify the residue.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00667% Admixed American · 4/59,988 alleles

Filtering AF 0.00511% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00468%

Overall 0.00489% 79/1,613,920 alleles · very rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.00667%	14,997
European (non-Finnish)	0.00627%	15,946
Remaining individualsnot grpmax-eligible	0.0016%	62,482

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: CKAP2
Protein: p.Arg281Trp
Coding: c.841C>T
MANE Select: NM_018204
dbSNP: rs200602489
Type: single nucleotide variant
Location: chr13:52461667 (GRCh38)
Gene constraint: LOEUF 0.983 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 59.29

Full CKAP2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

CKAP2 p.Arg628Gln Uncertain significance ★★ ⚠ same type
CKAP2 p.Asn386Asp Benign ★★ same type
CKAP2 p.Thr312= Benign ★★ same type
CKAP2 p.Ala214Ser Uncertain significance ★ ⚠ same type
CKAP2 p.Ala326Thr Uncertain significance ★ ⚠ same type
CKAP2 p.Ala347Ser Uncertain significance ★ ⚠ same type
CKAP2 p.Ala350Thr Uncertain significance ★ ⚠ same type
CKAP2 p.Ala614Ser 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/ckap2-p-arg281trp (accessed [today's date]).

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