Is SCN2A p.Pro283= (c.849A>G) pathogenic?

SCN2A p.Pro283= (c.849A>G) is classified Likely benign in SCN2A (ClinVar, Single submitter, 1 submitter; last evaluated 2022-12-10). Very rare (popmax 0.00267%, afr); Associated with developmental and epileptic encephalopathy, 11.

What condition is associated with SCN2A p.Pro283= (c.849A>G)?

SCN2A p.Pro283= (c.849A>G) is associated with developmental and epileptic encephalopathy, 11, seizures, benign familial infantile, 3 (ClinVar).

How common is SCN2A p.Pro283= (c.849A>G) in the general population?

SCN2A p.Pro283= (c.849A>G) is very rare (popmax 0.00267%, afr) (gnomAD).

SCN2A p.Pro283=

c.849A>G · rs1697368581 · VCV1666155

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00267%, afr)

Conditions

developmental and epileptic encephalopathy, 11

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 1.4	GERP -2.2, phastCons 1
Overall
CADD	7.727	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00267% African / African-American · 2/74,888 alleles

Filtering AF 0.000443% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000166%

Overall 0.00131% 2/152,142 alleles · very rare

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: SCN2A
Protein: p.Pro283=
Coding: c.849A>G
MANE Select: NM_001040142
dbSNP: rs1697368581
Type: single nucleotide variant
Location: chr2:165310474 (GRCh38)
Gene constraint: LOEUF 0.161 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 69.28 · 5 PDB
Residue 283: a disulfide bond; a UniProt-annotated variant site (found in a patient with intractable epilepsy and severe mental decline; likely pathogenic; non-conducting; loss of voltage-gated sodium channel activity; dominant-negative); a UniProt-annotated variant site (found in a patient with schizofrenia; uncertain significance)

Full SCN2A gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

developmental and epileptic encephalopathy, 11 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: seizures, benign familial infantile, 3

Similar variants

SCN2A p.Pro283Ala Uncertain significance ★★ ⚠ same residue
SCN2A p.Ala1773Thr Pathogenic ★★★ same condition
SCN2A p.Arg220Gly Likely pathogenic ★★★ same condition
SCN2A p.Arg853Gln Pathogenic ★★★ same condition
SCN2A p.Gly899Asp Likely pathogenic ★★★ same condition
SCN2A p.Leu1611Pro Pathogenic ★★★ same condition
SCN2A p.Leu886Ser Likely pathogenic ★★★ same condition
SCN2A p.Lys1260Glu 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/scn2a-p-pro283 (accessed [today's date]).

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