1-40838474-C-G

Variant names:

• chr1-40838474-C-G
• rs772135867
• NM_004700.4:c.2039C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004700.4(KCNQ4):​c.2039C>G​(p.Ser680Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,798 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S680F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KCNQ4 NM_004700.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.07
• Publications: 0 publications found

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]

KCNQ4 Gene-Disease associations (from GenCC):

• autosomal dominant nonsyndromic hearing loss 2A

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• nonsyndromic genetic hearing loss

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• autosomal dominant nonsyndromic hearing loss

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hearing loss disorder

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.826

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004700.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNQ4	NM_004700.4	MANE Select	c.2039C>G	p.Ser680Cys	missense	Exon 14 of 14	NP_004691.2
	KCNQ4	NM_172163.3		c.1877C>G	p.Ser626Cys	missense	Exon 13 of 13	NP_751895.1	P56696-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNQ4	ENST00000347132.10	TSL:1 MANE Select	c.2039C>G	p.Ser680Cys	missense	Exon 14 of 14	ENSP00000262916.6	P56696-1
	KCNQ4	ENST00000967337.1		c.1979C>G	p.Ser660Cys	missense	Exon 14 of 14	ENSP00000637396.1
	KCNQ4	ENST00000967338.1		c.1922C>G	p.Ser641Cys	missense	Exon 14 of 14	ENSP00000637397.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461798 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727220

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111946

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.43	T
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	2.0	M
PhyloP100		6.1
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-2.1	N
REVEL	Pathogenic	0.66
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.015	D
Polyphen		1.0	D
Vest4		0.56
MutPred		0.35		Loss of disorder (P = 0)
MVP		0.78
MPC		2.1
ClinPred		0.94	D
GERP RS		4.9
Varity_R		0.23
gMVP		0.65
Mutation Taster		=25/75	disease causing

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

Other links and lift over

dbSNP: rs772135867; hg19: chr1-41304146;