1-40784203-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_004700.4(KCNQ4):c.110G>A(p.Gly37Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000679 in 147,254 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000068 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: KCNQ4 NM_004700.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.32

Genes affected

KCNQ4 (HGNC:6298): (potassium voltage-gated channel subfamily Q member 4) The protein encoded by this gene forms a potassium channel that is thought to play a critical role in the regulation of neuronal excitability, particularly in sensory cells of the cochlea. The current generated by this channel is inhibited by M1 muscarinic acetylcholine receptors and activated by retigabine, a novel anti-convulsant drug. The encoded protein can form a homomultimeric potassium channel or possibly a heteromultimeric channel in association with the protein encoded by the KCNQ3 gene. Defects in this gene are a cause of nonsyndromic sensorineural deafness type 2 (DFNA2), an autosomal dominant form of progressive hearing loss. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.34905997).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ4	NM_004700.4	c.110G>A	p.Gly37Asp	missense_variant	1/14	ENST00000347132.10
KCNQ4	NM_172163.3	c.110G>A	p.Gly37Asp	missense_variant	1/13
KCNQ4	XM_047434057.1	c.110G>A	p.Gly37Asp	missense_variant	1/13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ4	ENST00000347132.10	c.110G>A	p.Gly37Asp	missense_variant	1/14	1	NM_004700.4	P2
KCNQ4	ENST00000509682.6	c.110G>A	p.Gly37Asp	missense_variant	1/13	5		A1

Frequencies

GnomAD3 genomes AF: 0.00000679 AC: 1 AN: 147254 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000245

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 980186 Hom.: 0 Cov.: 24 AF XY: 0.00 AC XY: 0 AN XY: 468466

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000679 AC: 1 AN: 147254 Hom.: 0 Cov.: 32 AF XY: 0.0000140 AC XY: 1 AN XY: 71652

Gnomad4 AFR AF: 0.0000245

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 29, 2023

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 37 of the KCNQ4 protein (p.Gly37Asp). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with KCNQ4-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KCNQ4 protein function with a positive predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.040
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Benign	0.33	T;T;.
Eigen	Benign	-0.23
Eigen_PC	Benign	-0.22
FATHMM_MKL	Uncertain	0.84	D
M_CAP	Pathogenic	0.97	D
MetaRNN	Benign	0.35	T;T;T
MetaSVM	Uncertain	0.78	D
MutationAssessor	Benign	0.75	N;N;N
MutationTaster	Benign	0.93	D;D
PrimateAI	Pathogenic	0.92	D
Polyphen		0.48	P;P;P
Vest4		0.13, 0.16
MutPred		0.23		Gain of solvent accessibility (P = 0.0638);Gain of solvent accessibility (P = 0.0638);Gain of solvent accessibility (P = 0.0638);
MVP		0.68
MPC		1.6
ClinPred		0.46	T
GERP RS		1.9
Varity_R		0.35
gMVP		0.56

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs983796218; hg19: chr1-41249875;