Is KAT2B p.Arg682Ter (c.2044C>T) pathogenic?

KAT2B p.Arg682Ter (c.2044C>T) is classified Uncertain significance in KAT2B (ClinVar, Single submitter, 1 submitter; last evaluated 2025-06-27). Very rare (popmax 0.000509%, nfe).

How common is KAT2B p.Arg682Ter (c.2044C>T) in the general population?

KAT2B p.Arg682Ter (c.2044C>T) is very rare (popmax 0.000509%, nfe) (gnomAD).

KAT2B p.Arg682Ter

c.2044C>T · VCV4885419

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.000509%, nfe)

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function in a LoF-intolerant gene
NMD	predicted	premature termination codon in exon 14 of 18
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 6	GERP 1.9, phastCons 1
Overall
CADD	45.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000509% European (non-Finnish) · 6/1,178,906 alleles

Filtering AF 0.000183% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00012%

Overall 0.000434% 7/1,612,530 alleles · very rare exomes 6/1,460,396 · genomes 1/152,134 · joint denominator

Ancestry group	Frequency	1 in
Finnishnot grpmax-eligible	0.00157%	63,884
European (non-Finnish)grpmax	0.000509%	196,484

Finnish shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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: KAT2B
Protein: p.Arg682Ter
Coding: c.2044C>T
MANE Select: NM_003884
Type: single nucleotide variant
Location: chr3:20146355 (GRCh38)
Gene constraint: LOEUF 0.461 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 78.22 · 25 PDB

Full KAT2B gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

KAT2B p.Arg682Gln Uncertain significance ★ ⚠ same residue
KAT2B p.Ile198Val Uncertain significance ★★ ⚠ same type
KAT2B c.1043+115G>A Benign ★★ same type
KAT2B c.1044-72T>C Benign ★★ same type
KAT2B c.1151-47G>T Benign ★★ same type
KAT2B c.1623-40C>G Benign ★★ same type
KAT2B c.1861-37T>C Benign ★★ same type
KAT2B c.1861-98G>T Benign ★★ 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/kat2b-p-arg682ter (accessed [today's date]).

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