KCNT2

Chr 1AD

potassium sodium-activated channel subfamily T member 2

Also known as: DEE57, EIEE57, KCa4.2, KNa1.2, SLICK, SLO2.1

The protein functions as a sodium-activated and chloride-activated potassium channel that regulates neuronal excitability by producing outward rectifier K+ currents across the plasma membrane. Mutations cause developmental and epileptic encephalopathy 57, characterized by early-onset seizures and developmental delays. The condition follows autosomal dominant inheritance, and the gene is highly constrained against loss-of-function variants (LOEUF 0.374).

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
GOFmechanismADLOEUF 0.371 OMIM phenotype
Clinical SummaryKCNT2
Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.25) despite low pLI — interpret in context.
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GeneReview available — KCNT2
Authoritative clinical overview · Recommended first read
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Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Missense constrained — critical functional residues
LoF Constraint
0.37LOEUF
pLI 0.042
Z-score 5.74
OE 0.25 (0.170.37)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
3.56Z-score
OE missense 0.58 (0.530.64)
340 obs / 581.7 exp
Constrained

Highly missense-constrained (top ~0.1%)

Observed / Expected Ratios
LoF OE0.25 (0.170.37)
00.351.4
Missense OE0.58 (0.530.64)
00.61.4
Synonymous OE1.10
01.21.6
LoF obs/exp: 17 / 68.1Missense obs/exp: 340 / 581.7Syn Z: -1.10
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
limitedKCNT2-related developmental and infantile epileptic encephalopathyGOFAD
DN
0.6260th %ile
GOF
0.73top 25%
LOF
0.3065th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median · 1 literature citation
DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Literature Evidence

GOFDe novo gain-of-function variants in KCNT2 as a novel cause of developmental and epileptic encephalopathy.PMID:29740868

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

KCNT2 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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Key Publications
Landmark & review papers · by relevance
PubMed
Top 5 results · since 2015Search PubMed ↗