5-114362977-G-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4

The NM_021614.4(KCNN2):c.838G>T(p.Val280Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000377 in 1,590,404 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V280M) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

KCNN2
NM_021614.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.14

Variant links:

Genes affected

KCNN2 (HGNC:6291): (potassium calcium-activated channel subfamily N member 2) Action potentials in vertebrate neurons are followed by an afterhyperpolarization (AHP) that may persist for several seconds and may have profound consequences for the firing pattern of the neuron. Each component of the AHP is kinetically distinct and is mediated by different calcium-activated potassium channels. The protein encoded by this gene is activated before membrane hyperpolarization and is thought to regulate neuronal excitability by contributing to the slow component of synaptic AHP. This gene is a member of the KCNN family of potassium channel genes. The encoded protein is an integral membrane protein that forms a voltage-independent calcium-activated channel with three other calmodulin-binding subunits. Alternate splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

KCNN2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.3423762).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNN2	NM_021614.4 linkuse as main transcript	c.838G>T	p.Val280Leu	missense_variant	1/8	ENST00000673685.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
KCNN2	ENST00000673685.1 linkuse as main transcript	c.838G>T	p.Val280Leu	missense_variant	1/8		NM_021614.4	P2
KCNN2	ENST00000512097.10 linkuse as main transcript	c.1036G>T	p.Val346Leu	missense_variant	6/13	5		A2
KCNN2	ENST00000631899.2 linkuse as main transcript	c.241G>T	p.Val81Leu	missense_variant	1/9	5

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152078

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000139

AC:

AN:

1438326

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

715088

show subpopulations

Gnomad4 AFR exome

AF:

0.0000301

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:

9.04e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152078

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74266

show subpopulations

Gnomad4 AFR

AF:

0.0000483

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:

0.0000294

Gnomad4 OTH

AF:

0.00

ESP6500AA

AF:

0.000228

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.00000830

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 16, 2022

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. This variant has not been reported in the literature in individuals affected with KCNN2-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 68 of the KCNN2 protein (p.Val68Leu). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.46

BayesDel_addAF

Pathogenic

0.17

BayesDel_noAF

Uncertain

0.010

Cadd

Uncertain

Dann

Uncertain

0.99

Eigen

Benign

0.19

Eigen_PC

Uncertain

0.36

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.91

D;D

M_CAP

Pathogenic

0.36

MetaRNN

Benign

0.34

T;T

MetaSVM

Pathogenic

0.83

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.95

REVEL

Uncertain

0.42

Polyphen

0.0070

.;B

Vest4

0.17

MutPred

0.21

.;Loss of methylation at K70 (P = 0.0786);

MVP

0.69

MPC

0.16

ClinPred

0.53

GERP RS

5.6

Varity_R

0.19

gMVP

0.59

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over