rs878854483

Variant names:

• chr1-160042471-A-G
• rs878854483
• NM_002241.5:c.62T>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_002241.5(KCNJ10):​c.62T>C​(p.Met21Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,860 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict 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. M21I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: KCNJ10 NM_002241.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.45
• Publications: 0 publications found

Genes affected

KCNJ10 (HGNC:6256): (potassium inwardly rectifying channel subfamily J member 10) This gene encodes a member of the inward rectifier-type potassium channel family, characterized by having a greater tendency to allow potassium to flow into, rather than out of, a cell. The encoded protein may form a heterodimer with another potassium channel protein and may be responsible for the potassium buffering action of glial cells in the brain. Mutations in this gene have been associated with seizure susceptibility of common idiopathic generalized epilepsy syndromes. [provided by RefSeq, Jul 2008]

KCNJ10 Gene-Disease associations (from GenCC):

• EAST syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, PanelApp Australia, G2P, Labcorp Genetics (formerly Invitae), ClinGen
• Pendred syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• enlarged vestibular aqueduct syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 14 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Trascript score misZ: 2.7053 (below the threshold of 3.09). GenCC associations: The gene is linked to EAST syndrome, enlarged vestibular aqueduct syndrome, Pendred syndrome.
• BP4: Computational evidence support a benign effect (MetaRNN=0.15139133).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNJ10	NM_002241.5	c.62T>C	p.Met21Thr	missense_variant	Exon 2 of 2	ENST00000644903.1	NP_002232.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNJ10	ENST00000644903.1	c.62T>C	p.Met21Thr	missense_variant	Exon 2 of 2		NM_002241.5	ENSP00000495557.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461860 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727240

African (AFR) AF: 0.0000299 AC: 1 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: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111990

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Apr 22, 2019

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.M21T variant (also known as c.62T>C), located in coding exon 1 of the KCNJ10 gene, results from a T to C substitution at nucleotide position 62. The methionine at codon 21 is replaced by threonine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

EAST syndrome Uncertain:1

Jan 15, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 21 of the KCNJ10 protein (p.Met21Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KCNJ10-related conditions. ClinVar contains an entry for this variant (Variation ID: 239111). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt KCNJ10 protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.043	T
BayesDel_noAF	Benign	-0.30
CADD	Benign	19
DANN	Benign	0.94
DEOGEN2	Benign	0.12	.;.;T;T;.;T;T
Eigen	Benign	-0.32
Eigen_PC	Benign	-0.085
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.67	T;T;.;.;T;.;T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.15	T;T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.52	.;.;N;N;.;N;N
PhyloP100		3.4
PrimateAI	Benign	0.41	T
PROVEAN	Benign	-0.20	.;.;.;N;.;.;.
REVEL	Benign	0.17
Sift	Benign	0.043	.;.;.;D;.;.;.
Sift4G	Uncertain	0.022	.;.;.;D;.;.;.
Polyphen		0.010	.;.;B;B;.;B;B
Vest4		0.078
MutPred		0.35		Gain of relative solvent accessibility (P = 0.005);Gain of relative solvent accessibility (P = 0.005);Gain of relative solvent accessibility (P = 0.005);Gain of relative solvent accessibility (P = 0.005);.;Gain of relative solvent accessibility (P = 0.005);Gain of relative solvent accessibility (P = 0.005);
MVP		0.44
MPC		0.61
ClinPred		0.27	T
GERP RS		5.2
PromoterAI		0.015	Neutral
Varity_R		0.29
gMVP		0.56
Mutation Taster		=70/30	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: rs878854483; hg19: chr1-160012261;