NM_004700.4:c.857A>C

Variant names:

• chr1-40819897-A-C
• rs876657841
• NM_004700.4:c.857A>C

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_004700.4(KCNQ4):​c.857A>C​(p.Tyr286Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y286C) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: KCNQ4 NM_004700.4 missense
• Clinical Significance: Likely pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.32
• 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_004700.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.966
• PP5: Variant 1-40819897-A-C is Pathogenic according to our data. Variant chr1-40819897-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1184480.Status of the report is no_assertion_criteria_provided, 0 stars.

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.857A>C	p.Tyr286Ser	missense	Exon 6 of 14	NP_004691.2
	KCNQ4	NM_172163.3		c.857A>C	p.Tyr286Ser	missense	Exon 6 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.857A>C	p.Tyr286Ser	missense	Exon 6 of 14	ENSP00000262916.6	P56696-1
	KCNQ4	ENST00000967337.1		c.857A>C	p.Tyr286Ser	missense	Exon 6 of 14	ENSP00000637396.1
	KCNQ4	ENST00000967338.1		c.857A>C	p.Tyr286Ser	missense	Exon 6 of 14	ENSP00000637397.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Autosomal dominant nonsyndromic hearing loss 2A (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.72	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		9.3
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-8.4	D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.77		Gain of glycosylation at Y286 (P = 0.0017)
MVP		1.0
MPC		2.6
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.99
gMVP		0.99
Mutation Taster		=4/96	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: rs876657841; hg19: chr1-41285569;