Is SMARCA4 p.Asp656= (c.1968T>C) pathogenic?

SMARCA4 p.Asp656= (c.1968T>C) is classified Benign/Likely benign in SMARCA4 (ClinVar, Multiple submitters, 5 submitters; last evaluated 2026-01-13). Ultra-rare (popmax 0.02%, amr); Associated with intellectual disability, autosomal dominant 16.

What condition is associated with SMARCA4 p.Asp656= (c.1968T>C)?

SMARCA4 p.Asp656= (c.1968T>C) is associated with intellectual disability, autosomal dominant 16, rhabdoid tumor predisposition syndrome 2, hereditary neoplastic syndrome (ClinVar).

How common is SMARCA4 p.Asp656= (c.1968T>C) in the general population?

SMARCA4 p.Asp656= (c.1968T>C) is ultra-rare (popmax 0.02%, amr) (gnomAD).

SMARCA4 p.Asp656=

c.1968T>C · rs750161079 · VCV415087

Benign/Likely benign Multiple submitters

Classification

Benign/Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 5 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.02%, amr)

Conditions

intellectual disability, autosomal dominant 16

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -4.3	GERP -4.1
Overall
CADD	3.744	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.02% Admixed American · 12/59,996 alleles

Filtering AF 0.0115% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00898%

Overall 0.0013% 21/1,614,000 alleles · ultra-rare exomes 18/1,461,816 · genomes 3/152,184 · joint denominator

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.02%	5,000
Remaining individualsnot grpmax-eligible	0.0032%	31,243
South Asian	0.0011%	91,082
European (non-Finnish)	0.000508%	196,663

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: SMARCA4
Protein: p.Asp656=
Coding: c.1968T>C
MANE Select: NM_003072
dbSNP: rs750161079
Type: single nucleotide variant
Location: chr19:11003364 (GRCh38)
Gene constraint: LOEUF 0.226 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 65.38 · 31 PDB
Residue 656: the 'disordered' region; the 'rna-binding region which is sufficient for binding to lncrna evf2' region

Full SMARCA4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

intellectual disability, autosomal dominant 16 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: rhabdoid tumor predisposition syndrome 2 hereditary neoplastic syndrome

Similar variants

SMARCA4 p.Asp656Val Uncertain significance ★★ ⚠ same residue
SMARCA4 c.1943+1G>A Likely pathogenic ★★ same condition
SMARCA4 c.2274+1G>T Likely pathogenic ★★ same condition
SMARCA4 c.2438+1G>A Pathogenic/Likely pathogenic ★★ same condition
SMARCA4 c.3216-1G>C Likely pathogenic ★★ same condition
SMARCA4 c.3216-2A>G Likely pathogenic ★★ same condition
SMARCA4 c.3546+1G>A Likely pathogenic ★★ same condition
SMARCA4 c.3774+2T>A 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/smarca4-p-asp656 (accessed [today's date]).

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