# KCNQ3

Source: https://onco.cc/targets/kcnq3/  
OnCo record `kcnq3` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

KCNQ3 (Potassium voltage-gated channel subfamily KQT member 3) is a gene. The public catalogues list it as a drug target, and an approved or late-stage drug is recorded against it.

## Summary

Pore-forming subunit of the voltage-gated potassium (Kv) M-channel which is responsible for the M-current, a key controller of neuronal excitability. M-channel is composed of pore-forming subunits KCNQ2 and KCNQ3 assembled as heterotetramers. The native M-current has a slowly activating and deactivating potassium conductance which plays a critical role in determining the subthreshold electrical excitability of neurons as well as the responsiveness to synaptic inputs.

Open Targets scores its association with cancer at 0.56 (direct and indirect evidence; datatypes literature 0.61, genetic association 0.41, somatic mutation 0.23, clinical 0.76).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: potassium voltage-gated channel subfamily Q member 3; Potassium voltage-gated channel subfamily KQT member 3; Kv7.3; EBN2
- Tags: cancer-genes-wave
- Symbol: KCNQ3
- Class: other
- Biology: Pore-forming subunit of the voltage-gated potassium (Kv) M-channel which is responsible for the M-current, a key controller of neuronal excitability. M-channel is composed of pore-forming subunits KCNQ2 and KCNQ3 assembled as heterotetramers. The native M-current has a slowly activating and deactivating potassium conductance which plays a critical role in determining the subthreshold electrical excitability of neurons as well as the responsiveness to synaptic inputs. M-channel is selectively permeable in vitro to other cations besides potassium, in decreasing order of affinity K(+) > Rb(+) > Cs(+) > Na(+). M-channel association with SLC5A3/SMIT1 alters channel ion selectivity, increasing Na(+) and Cs(+) permeation relative to K(+). Suppressed by activation of M1 muscarinic acetylcholine receptors. Location: Cell membrane (UniProt). Locus 8q24.22 (HGNC).

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: Open Targets known-drug datatype score 0.76. Evidence tier "approved-drug" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:6297: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6297
- UniProt O43525: https://www.uniprot.org/uniprotkb/O43525/entry
- NCBI Gene 3786: https://www.ncbi.nlm.nih.gov/gene/3786
- Ensembl ENSG00000184156: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000184156

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)

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JSON: https://onco.cc/api/v1/entities/kcnq3.json