KCNG4
Chr 16potassium voltage-gated channel modifier subfamily G member 4
Also known as: KV6.3, KV6.4
The KCNG4 protein functions as a regulatory subunit that modulates voltage-gated potassium channels by altering their activation, deactivation, and inactivation kinetics when coassembled with other channel subunits like KCNB1. Mutations in KCNG4 cause autosomal dominant spinocerebellar ataxia type 18, characterized by progressive cerebellar dysfunction. The gene shows autosomal dominant inheritance and has relatively low constraint to loss-of-function variation.
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Tolerant to missense variation
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.
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.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
KCNG4 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools