17-70169557-G-C

Variant names:

• chr17-70169557-G-C
• rs984704301
• NM_000891.3:c.-361G>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_Moderate BS1_Supporting

The NM_000891.3(KCNJ2):​c.-361G>C variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000263 in 152,260 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 (★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: KCNJ2 NM_000891.3 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:3
• Conservation: PhyloP100: 1.25
• Publications: 0 publications found

Genes affected

KCNJ2 (HGNC:6263): (potassium inwardly rectifying channel subfamily J member 2) Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, probably participates in establishing action potential waveform and excitability of neuronal and muscle tissues. Mutations in this gene have been associated with Andersen syndrome, which is characterized by periodic paralysis, cardiac arrhythmias, and dysmorphic features. [provided by RefSeq, Jul 2008]

KCNJ2-AS1 (HGNC:43720): (KCNJ2 antisense RNA 1)

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.41).
• BS1: Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.0000263 (4/152260) while in subpopulation EAS AF = 0.000779 (4/5138). AF 95% confidence interval is 0.000266. There are 0 homozygotes in GnomAd4. There are 2 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNJ2	NM_000891.3	c.-361G>C		5_prime_UTR_variant	Exon 1 of 2	ENST00000243457.4	NP_000882.1
KCNJ2-AS1	NR_036534.1	n.-155C>G		upstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNJ2	ENST00000243457.4	c.-361G>C		5_prime_UTR_variant	Exon 1 of 2	1	NM_000891.3	ENSP00000243457.2
KCNJ2	ENST00000535240.1	c.-217+700G>C		intron_variant	Intron 1 of 1	1		ENSP00000441848.1
KCNJ2-AS1	ENST00000590966.2	n.-153C>G		upstream_gene_variant		6

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152142 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000777

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

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 382 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 296

African (AFR) AF: 0.00 AC: 0 AN: 6

American (AMR) AF: 0.00 AC: 0 AN: 4

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 2

East Asian (EAS) AF: 0.00 AC: 0 AN: 6

South Asian (SAS) AF: 0.00 AC: 0 AN: 4

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 6

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 6

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 338

Other (OTH) AF: 0.00 AC: 0 AN: 10

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152260 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74436

African (AFR) AF: 0.00 AC: 0 AN: 41576

American (AMR) AF: 0.00 AC: 0 AN: 15306

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000779 AC: 4 AN: 5138

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10618

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: 2112

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, single submitter

Submissions by phenotype

Atrial fibrillation, familial, 9 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Andersen Tawil syndrome Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Short QT syndrome type 3 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.41
CADD	Benign	17
DANN	Benign	0.91
PhyloP100		1.3
PromoterAI		0.025	Neutral

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: rs984704301; hg19: chr17-68165698;