rs558502886

chr1-160041881-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_002241.5(KCNJ10):c.652C>T(p.Leu218Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,614,222 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000020 (0 hom.)
• Consequence: KCNJ10 NM_002241.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 8.15

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.87

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNJ10	NM_002241.5	c.652C>T	p.Leu218Phe	missense_variant	2/2	ENST00000644903.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNJ10	ENST00000644903.1	c.652C>T	p.Leu218Phe	missense_variant	2/2		NM_002241.5	P1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152230 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000159 AC: 4 AN: 251298 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135810

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000198 AC: 29 AN: 1461874 Hom.: 0 Cov.: 32 AF XY: 0.0000220 AC XY: 16 AN XY: 727236

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000899

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152348 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74506

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.0000653

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000658 Hom.: 0

Bravo AF: 0.0000113

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

EAST syndrome Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 22, 2022	This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 218 of the KCNJ10 protein (p.Leu218Phe). This variant is present in population databases (rs558502886, gnomAD 0.009%). This missense change has been observed in individual(s) with severe epilepsy and profound developmental delay (PMID: 28747464). ClinVar contains an entry for this variant (Variation ID: 205829). 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: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). Experimental studies have shown that this missense change affects KCNJ10 function (PMID: 28747464). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Al Jalila Children's Genomics Center, Al Jalila Childrens Speciality Hospital	Sep 24, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Sep 19, 2016

A variant of uncertain significance has been identified in the KCNJ10 gene. The L218F variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The L218F variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project and was not observed with any significant frequency in the 1000 Genomes Project. The L218F variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. However, this substitution occurs at a position that is conserved across species, and in silico analysis predicts this variant is probably damaging to the protein structure/function. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Autosomal recessive nonsyndromic hearing loss 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Pendred syndrome;C2748572:EAST syndrome;C3538946:Autosomal recessive nonsyndromic hearing loss 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 06, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.76
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.36
Cadd	Pathogenic	29
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.89	D;D;.;D;D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.29	D
MetaRNN	Pathogenic	0.87	D;D;D;D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Uncertain	2.3	M;M;.;M;M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.78	T
Polyphen		1.0	D;D;.;D;D
Vest4		0.67
MVP		0.85
MPC		1.4
ClinPred		0.97	D
GERP RS		5.3
Varity_R		0.73
gMVP		0.71

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: rs558502886; hg19: chr1-160011671;