KCNMB1
protein-codingpotassium calcium-activated channel subfamily M regulatory beta subunit 1, the group of Potassium calcium-activated channel subfamily M regulatory beta subunits
Gene summary
MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the product of this gene, the modulatory beta subunit. Intracellular calcium regulates the physical association between the alpha and beta subunits. [provided by RefSeq, Jul 2008]
MANE transcript
Inheritance
ClinVar variants
Top phenotype
gnomAD constraint
Max pathogenic AF
Genomic locus
External References & Databases
Transcript & Mutation Effects
hg38 • Region Span ~15.0 kbGenCC Phenotypes & Disease Associations
Curated gene-disease validity assertions and inheritance patterns
No GenCC data available for this gene.
ClinVar Associated Diseases & Phenotypes
Reported disease conditions connected to KCNMB1 variants in ClinVar
ClinVar Variants & Pathogenicity by Type
Statistics based on transcript NM_004137.4. Only rare variants are included.
We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.
Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.
| Effect | PathogenicP | Likely pathogenicLP | VUS | Likely benignLB | BenignB | Sum |
|---|---|---|---|---|---|---|
| synonymous | 2 | 1 | 3 | |||
| missense | 34 | 1 | 1 | 36 | ||
| nonsense | 0 | |||||
| start loss | 0 | |||||
| frameshift | 0 | |||||
| splice donor/acceptor (+/-2bp) | 1 | 1 | ||||
| Total | 0 | 0 | 35 | 3 | 2 | 40 |
Transcript Catalog
Annotated transcript isoforms across RefSeq and Ensembl databases
| Transcript ID | Source | Protein ID | Coding Exons | MANE Status |
|---|---|---|---|---|
| RefSeq | NP_004128.1 | 3 | MANE Select | |
| Ensembl | ENSP00000274629.3 | 3 | MANE Select | |
| Ensembl | ENSP00000427940.1 | 2 | Standard | |
| Ensembl | ENSP00000427940.1 | 2 | Standard |
Gene Ontology (GO) Annotations & Pathways
Biological processes, molecular functions, cellular components and pathways
Pathways ConsensusPathDB
- Vascular smooth muscle contraction - Homo sapiens (human)
- cGMP-PKG signaling pathway - Homo sapiens (human)
- Insulin secretion - Homo sapiens (human)
- Neuronal System
- Hemostasis
Biological Process
- detection of calcium ion
- potassium ion transport
- chemical synaptic transmission
- aging
- cellular response to ethanol
Molecular Function
- calcium-activated potassium channel activity
- potassium channel regulator activity
Cellular Component
- plasma membrane
- voltage-gated potassium channel complex
gnomAD Constraint
Source:
- Gene type
- protein_coding
- Transcript type
- protein_coding
- Transcript
- ENST00000274629
- Coding exons
- 3
- Length
- 15007
- Individuals with no LoFs
- 125685
- Homozygous LoFs
- 0
- Heterozygous LoFs
- 63
- Defined
- 125748
- p
- 0.000251
| Z-Score | Observed | Expected | Observed/Expected | Mutation Rate | Total Possible | |
|---|---|---|---|---|---|---|
| Missense | 0.219 | 112 | 119 | 0.944 | 0.00000734 | 1223 |
| Missense (PolyPhen) | 55 | 52.203 | 1.0536 | 502 | ||
| Synonymous | -0.0321 | 56 | 55.7 | 1.01 | 0.00000382 | 395 |
| Loss of Function | 0.188 | 9 | 9.63 | 0.935 | 5.13e-7 | 93 |
Population LoF Frequency
| Population | CAF | p-value | Status |
|---|---|---|---|
| African | 0.00018 | 0.00018 | rare |
| Latino/Admixed American | 0.00032 | 0.00032 | rare |
| Ashkenazi Jewish | 0 | 0.0 | absent |
| East Asian | 0.00016 | 0.00016 | rare |
| Finnish | 0.000092 | 0.000092 | rare |
| European (Non-Finnish) | 0.00034 | 0.00034 | rare |
| South Asian | 0.00013 | 0.00013 | rare |
| Other | 0.00016 | 0.00016 | rare |
dbNSFP Gene Annotations
Source:
- Function
- FUNCTION: Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Increases the apparent Ca(2+)/voltage sensitivity of the KCNMA1 channel. It also modifies KCNMA1 channel kinetics and alters its pharmacological properties. It slows down the activation and the deactivation kinetics of the channel. Acts as a negative regulator of smooth muscle contraction by enhancing the calcium sensitivity to KCNMA1. Its presence is also a requirement for internal binding of the KCNMA1 channel opener dehydrosoyasaponin I (DHS-1) triterpene glycoside and for external binding of the agonist hormone 17-beta-estradiol (E2). Increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1 peptide blocker by increasing the CTX association rate and decreasing the dissociation rate.;
Recessive Scores
- pRec
- 0.136
Intolerance Scores
- LoFtool
- 0.731
- RVIS EVS
- 0.35
- RVIS percentile EVS
- 74.37
Essentials
- Essential (CRISPR)
- N
- Essential (CRISPR2)
- N
- Essential (gene trap)
- N
- Indispensability pred.
- E
- Indispensability score
- 0.754
Gene Damage Prediction
| All | Recessive | Dominant | |
|---|---|---|---|
| Mendelian | Medium | Medium | Medium |
| Primary Immunodeficiency | Medium | Medium | Medium |
| Cancer | Medium | Medium | Medium |