Is CHD2 p.Arg900= (c.2700A>G) pathogenic?

CHD2 p.Arg900= (c.2700A>G) is classified Likely benign in CHD2 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-10-17). Very rare (popmax 0.00329%, sas); Associated with developmental and epileptic encephalopathy 94.

What condition is associated with CHD2 p.Arg900= (c.2700A>G)?

CHD2 p.Arg900= (c.2700A>G) is associated with developmental and epileptic encephalopathy 94 (ClinVar).

How common is CHD2 p.Arg900= (c.2700A>G) in the general population?

CHD2 p.Arg900= (c.2700A>G) is very rare (popmax 0.00329%, sas) (gnomAD).

How is Lennox-Gastaut syndrome inherited?

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

CHD2 p.Arg900=

c.2700A>G · rs770659670 · VCV1956743

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00329%, sas)

Conditions

developmental and epileptic encephalopathy 94

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 1.8	GERP -3.1, phastCons 1
Overall
CADD	8.268	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00329% South Asian · 3/91,076 alleles

Filtering AF 0.000875% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000443%

Overall 0.00031% 5/1,613,976 alleles · very rare exomes 5/1,461,858 · genomes 0/152,118 · joint denominator

Ancestry group	Frequency	1 in
South Asiangrpmax	0.00329%	30,359
European (non-Finnish)	0.000169%	590,012

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: CHD2
Protein: p.Arg900=
Coding: c.2700A>G
MANE Select: NM_001271
dbSNP: rs770659670
Type: single nucleotide variant
Location: chr15:92978356 (GRCh38)
Gene constraint: LOEUF 0.174 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 60.81
Residue 900: the helicase c-terminal domain; 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.Arg900Gln Pathogenic/Likely pathogenic ★★ same residue
CHD2 p.Arg900Ter Pathogenic ★★ same residue
CHD2 p.Arg900Gly Pathogenic ★ same residue
CHD2 p.Arg900Leu Likely pathogenic ★ same residue
CHD2 p.Arg900Pro Likely pathogenic ★ 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

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-arg900 (accessed [today's date]).

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