11-64293095-C-T

Position:

• chr11-64293095-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The ENST00000422670.7(KCNK4):​c.77C>T​(p.Ala26Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000716 in 1,396,062 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 7.2e-7 (0 hom.)
• Consequence: KCNK4 ENST00000422670.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.33

Genes affected

KCNK4 (HGNC:6279): (potassium two pore domain channel subfamily K member 4) This gene encodes a member of the TWIK-related arachidonic acid-stimulated two pore potassium channel subfamily. The encoded protein homodimerizes and functions as an outwardly rectifying channel. This channel is regulated by polyunsaturated fatty acids, temperature and mechanical deformation of the lipid membrane. This protein is expressed primarily in neural tissues and may be involved in regulating the noxious input threshold in dorsal root ganglia neurons. Alternate splicing results in multiple transcript variants. Naturally occurring read-through transcripts also exist between this gene and the downstream testis expressed 40 (TEX40) gene, as represented in GeneID: 106780802. [provided by RefSeq, Nov 2015]

KCNK4-TEX40 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11020094).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNK4	NM_033310.3	c.77C>T	p.Ala26Val	missense_variant	2/7	ENST00000422670.7	NP_201567.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNK4	ENST00000422670.7	c.77C>T	p.Ala26Val	missense_variant	2/7	1	NM_033310.3	ENSP00000402797.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.16e-7 AC: 1 AN: 1396062 Hom.: 0 Cov.: 31 AF XY: 0.00000145 AC XY: 1 AN XY: 688514

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: 9.28e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

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

Labcorp Genetics (formerly Invitae), Labcorp

Sep 21, 2021

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available"). This variant has not been reported in the literature in individuals affected with KCNK4-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with valine at codon 26 of the KCNK4 protein (p.Ala26Val). The alanine residue is moderately conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.095
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.45
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.064	T;T;T
Eigen	Benign	0.047
Eigen_PC	Benign	0.10
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Pathogenic	0.98	.;.;D
M_CAP	Benign	0.0085	T
MetaRNN	Benign	0.11	T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.8	L;L;L
MutationTaster	Benign	1.0	D;N;N;N
PrimateAI	Uncertain	0.60	T
PROVEAN	Benign	-0.90	N;N;N
REVEL	Benign	0.069
Sift	Benign	0.44	T;T;T
Sift4G	Benign	0.34	T;T;T
Polyphen		0.59	P;P;P
Vest4		0.33
MutPred		0.40		Loss of disorder (P = 0.0963);Loss of disorder (P = 0.0963);Loss of disorder (P = 0.0963);
MVP		0.72
MPC		0.23
ClinPred		0.43	T
GERP RS		3.3
Varity_R		0.11
gMVP		0.30

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: rs2034679555; hg19: chr11-64060567;