rs181746838

Variant names:

• chr8-132129753-A-G
• rs181746838
• NM_004519.4:c.2128T>C

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_Strong BP6_Very_Strong BS1

The NM_004519.4(KCNQ3):​c.2128T>C​(p.Tyr710His) variant causes a missense change. The variant allele was found at a frequency of 0.0000378 in 1,614,084 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 Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y710C) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000035 (0 hom.)
• Consequence: KCNQ3 NM_004519.4 missense
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 3.99
• Publications: 4 publications found

Genes affected

KCNQ3 (HGNC:6297): (potassium voltage-gated channel subfamily Q member 3) This gene encodes a protein that functions in the regulation of neuronal excitability. The encoded protein forms an M-channel by associating with the products of the related KCNQ2 or KCNQ5 genes, which both encode integral membrane proteins. M-channel currents are inhibited by M1 muscarinic acetylcholine receptors and are activated by retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of benign familial neonatal convulsions type 2 (BFNC2), also known as epilepsy, benign neonatal type 2 (EBN2). Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2014]

KCNQ3 Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• seizures, benign familial neonatal, 2

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• self-limited familial neonatal epilepsy

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• benign familial infantile epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• benign neonatal seizures

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• genetic developmental and epileptic encephalopathy

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics, ClinGen

ACMG classification

Our verdict: Benign. The variant received -16 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.022190958).
• BP6: Variant 8-132129753-A-G is Benign according to our data. Variant chr8-132129753-A-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 205984.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.0000657 (10/152192) while in subpopulation EAS AF = 0.00175 (9/5154). AF 95% confidence interval is 0.00091. There are 0 homozygotes in GnomAd4. There are 4 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004519.4. 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
	KCNQ3	NM_004519.4	MANE Select	c.2128T>C	p.Tyr710His	missense	Exon 15 of 15	NP_004510.1	O43525-1
	KCNQ3	NM_001204824.2		c.1768T>C	p.Tyr590His	missense	Exon 15 of 15	NP_001191753.1	O43525-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNQ3	ENST00000388996.10	TSL:1 MANE Select	c.2128T>C	p.Tyr710His	missense	Exon 15 of 15	ENSP00000373648.3	O43525-1
	KCNQ3	ENST00000519445.5	TSL:5	c.2092T>C	p.Tyr698His	missense	Exon 15 of 15	ENSP00000428790.1	E7ET42
	KCNQ3	ENST00000521134.6	TSL:2	c.1768T>C	p.Tyr590His	missense	Exon 15 of 15	ENSP00000429799.1	O43525-2

Frequencies

GnomAD3 genomes AF: 0.0000658 AC: 10 AN: 152074 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00174

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

GnomAD2 exomes AF: 0.0000796 AC: 20 AN: 251372 AF XY: 0.0000589

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00103

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.0000349 AC: 51 AN: 1461892 Hom.: 0 Cov.: 32 AF XY: 0.0000220 AC XY: 16 AN XY: 727248

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.000680 AC: 27 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112010

Other (OTH) AF: 0.000381 AC: 23 AN: 60396

GnomAD4 genome AF: 0.0000657 AC: 10 AN: 152192 Hom.: 0 Cov.: 32 AF XY: 0.0000537 AC XY: 4 AN XY: 74422

African (AFR) AF: 0.00 AC: 0 AN: 41538

American (AMR) AF: 0.0000654 AC: 1 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00175 AC: 9 AN: 5154

South Asian (SAS) AF: 0.00 AC: 0 AN: 4812

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68004

Other (OTH) AF: 0.00 AC: 0 AN: 2106

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000340

ExAC AF: 0.0000659 AC: 8

Asia WGS AF: 0.00346 AC: 12 AN: 3478

ClinVar

ClinVar submissions

Significance: Benign/Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	1	Benign neonatal seizures (1)
-	-	1	Inborn genetic diseases (1)
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Uncertain	-0.030
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Benign	0.34	T
Eigen	Benign	-0.23
Eigen_PC	Benign	-0.15
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.91	D
M_CAP	Uncertain	0.097	D
MetaRNN	Benign	0.022	T
MetaSVM	Uncertain	0.69	D
MutationAssessor	Benign	1.0	L
PhyloP100		4.0
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	0.29	N
REVEL	Uncertain	0.42
Sift	Benign	0.060	T
Sift4G	Benign	0.49	T
Polyphen		0.94	P
Vest4		0.35
MVP		0.54
MPC		0.32
ClinPred		0.11	T
GERP RS		4.5
Varity_R		0.098
gMVP		0.50
Mutation Taster		=88/12	polymorphism

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: rs181746838; hg19: chr8-133142000; COSMIC: COSV66470193;