10-117197506-C-T

Variant names:

• chr10-117197506-C-T
• rs1274147777
• NM_181840.1:c.18C>T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_181840.1(KCNK18):​c.18C>T​(p.His6His) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,900 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KCNK18 NM_181840.1 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -2.08

Genes affected

KCNK18 (HGNC:19439): (potassium two pore domain channel subfamily K member 18) Potassium channels play a role in many cellular processes including maintenance of the action potential, muscle contraction, hormone secretion, osmotic regulation, and ion flow. This gene encodes a member of the superfamily of potassium channel proteins containing two pore-forming P domains and the encoded protein functions as an outward rectifying potassium channel. A mutation in this gene has been found to be associated with migraine with aura.[provided by RefSeq, Jan 2011]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.9).
• BP7: Synonymous conserved (PhyloP=-2.08 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNK18	NM_181840.1	c.18C>T	p.His6His	synonymous_variant	Exon 1 of 3	ENST00000334549.1	NP_862823.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNK18	ENST00000334549.1	c.18C>T	p.His6His	synonymous_variant	Exon 1 of 3	1	NM_181840.1	ENSP00000334650.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460900 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726724

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.90
CADD	Benign	0.082
DANN	Benign	0.43

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: rs1274147777; hg19: chr10-118957017; COSMIC: COSV57970500; COSMIC: COSV57970500;