rs763135225

Positions:

• chr1-110604465-T-C

Variant summary

Our verdict is Benign. Variant got -15 ACMG points: 0P and 15B. BP4_Strong BP6_Moderate BP7 BS1 BS2

The NM_004974.4(KCNA2):​c.318A>G​(p.Leu106=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,064 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 Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.000039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: KCNA2 NM_004974.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -1.75

Genes affected

KCNA2 (HGNC:6220): (potassium voltage-gated channel subfamily A member 2) Potassium channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shaker-related subfamily. This member contains six membrane-spanning domains with a shaker-type repeat in the fourth segment. It belongs to the delayed rectifier class, members of which allow nerve cells to efficiently repolarize following an action potential. The coding region of this gene is intronless, and the gene is clustered with genes KCNA3 and KCNA10 on chromosome 1. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Benign. Variant got -15 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.52).
• BP6: Variant 1-110604465-T-C is Benign according to our data. Variant chr1-110604465-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 476052.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-1.75 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0000394 (6/152188) while in subpopulation AFR AF= 0.000145 (6/41424). AF 95% confidence interval is 0.0000629. There are 0 homozygotes in gnomad4. There are 3 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNA2	NM_004974.4	c.318A>G	p.Leu106=	synonymous_variant	3/3	ENST00000316361.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNA2	ENST00000316361.10	c.318A>G	p.Leu106=	synonymous_variant	3/3	2	NM_004974.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000394 AC: 6 AN: 152188 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000145

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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251390 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135898

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.00

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461876 Hom.: 0 Cov.: 34 AF XY: 0.00000275 AC XY: 2 AN XY: 727238

Gnomad4 AFR exome AF: 0.000179

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 AF: 0.0000394 AC: 6 AN: 152188 Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3 AN XY: 74344

Gnomad4 AFR AF: 0.000145

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: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000378

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 32 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jun 11, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.52
CADD	Benign	12
DANN	Benign	0.69

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs763135225; hg19: chr1-111147087;