Is CHD2 p.Tyr1143Cys (c.3428A>G) pathogenic?

CHD2 p.Tyr1143Cys (c.3428A>G) is classified Likely pathogenic in CHD2 (ClinVar, Single submitter, 1 submitter; last evaluated 2024-06-16). AlphaMissense: likely pathogenic (0.8223); Absent from gnomAD v4.1; Associated with developmental and epileptic encephalopathy 94.

What condition is associated with CHD2 p.Tyr1143Cys (c.3428A>G)?

CHD2 p.Tyr1143Cys (c.3428A>G) is associated with developmental and epileptic encephalopathy 94 (ClinVar).

How common is CHD2 p.Tyr1143Cys (c.3428A>G) in the general population?

CHD2 p.Tyr1143Cys (c.3428A>G) is absent from gnomAD v4.1 (gnomAD).

How is Lennox-Gastaut syndrome inherited?

Typically Autosomal dominant, Multigenic/multifactorial (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about CHD2 p.Tyr1143Cys (c.3428A>G)?

AlphaMissense predicts likely pathogenic (score 0.8223) — an in-silico prediction, not a clinical call.

CHD2 p.Tyr1143Cys

c.3428A>G · rs2505576945 · VCV3242411

Likely pathogenic Single submitter

Classification

Likely pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.8223 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

developmental and epileptic encephalopathy 94

Computational evidence

Protein change
AlphaMissense	0.8223	likely pathogenic ✓ concordant with ClinVar
REVEL	0.806	moderately pathogenic-leaning
SaProt	LLR -11.50	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 11	GERP 1.7, phastCons 1
Regional constraint	o/e 0.23	constrained · MANE · 7,276 bp · p 4.1e-09 · regional, not allelic
Overall
CADD	27.6	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: CHD2
Protein: p.Tyr1143Cys
Coding: c.3428A>G
MANE Select: NM_001271
dbSNP: rs2505576945
Type: single nucleotide variant
Location: chr15:92991490 (GRCh38)
Gene constraint: LOEUF 0.174 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 60.81
Residue 1143: a UniProt-annotated variant site (in dee94); a UniProt-annotated variant site (found in a patient with progressive myoclonus epilepsy; uncertain significance)

Full CHD2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

developmental and epileptic encephalopathy 94 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Lennox-Gastaut syndrome (Orphanet):

Inheritance: Autosomal dominant, Multigenic/multifactorial, Not applicable
Onset: Childhood, Infancy
Prevalence: 1-9 / 1 000 000 (Europe)

Similar variants

CHD2 p.Tyr1143Asp Conflicting classifications of pathogenicity ★ ⚠ same residue
CHD2 c.1153+1G>C Pathogenic ★★ same condition
CHD2 c.1809+1G>A Pathogenic/Likely pathogenic ★★ same condition
CHD2 c.294+1G>T Likely pathogenic ★★ same condition
CHD2 c.443+1G>A Pathogenic/Likely pathogenic ★★ same condition
CHD2 c.693-1G>A Likely pathogenic ★★ same condition
CHD2 p.Ala879Val Pathogenic/Likely pathogenic ★★ ⚠ same condition
CHD2 p.Arg1072Ter 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/chd2-p-tyr1143cys (accessed [today's date]).

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