1-110601794-A-T

Variant names:

• chr1-110601794-A-T
• rs112410383
• NM_004974.4:c.*1489T>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_004974.4(KCNA2):​c.*1489T>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. 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: 𝑓 0.0000074 (0 hom., cov: 20)
• Consequence: KCNA2 NM_004974.4 3_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.354
• Publications: 0 publications found

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]

KCNA2 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 32

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.92).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNA2	NM_004974.4	c.*1489T>A		3_prime_UTR_variant	Exon 3 of 3	ENST00000316361.10	NP_004965.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNA2	ENST00000316361.10	c.*1489T>A		3_prime_UTR_variant	Exon 3 of 3	2	NM_004974.4	ENSP00000314520.4

Frequencies

GnomAD3 genomes AF: 0.00000736 AC: 1 AN: 135930 Hom.: 0 Cov.: 20

Gnomad AFR AF: 0.00

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: 0.0000154

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 11

GnomAD4 genome AF: 0.00000736 AC: 1 AN: 135930 Hom.: 0 Cov.: 20 AF XY: 0.0000153 AC XY: 1 AN XY: 65390

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 34308

American (AMR) AF: 0.00 AC: 0 AN: 13446

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3330

East Asian (EAS) AF: 0.00 AC: 0 AN: 4478

South Asian (SAS) AF: 0.00 AC: 0 AN: 4080

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 8376

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000154 AC: 1 AN: 64864

Other (OTH) AF: 0.00 AC: 0 AN: 1878

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.92
CADD	Benign	1.6
DANN	Benign	0.44
PhyloP100		-0.35

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: rs112410383; hg19: chr1-111144416;