12-5045501-G-C

Variant names:

• chr12-5045501-G-C
• rs1486417435
• NM_002234.4:c.1354G>C

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_002234.4(KCNA5):​c.1354G>C​(p.Val452Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000109 in 1,461,892 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: KCNA5 NM_002234.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.86

Genes affected

KCNA5 (HGNC:6224): (potassium voltage-gated channel subfamily A member 5) Potassium channels represent the most complex class of voltage-gated ino 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, the function of which could restore the resting membrane potential of beta cells after depolarization and thereby contribute to the regulation of insulin secretion. This gene is intronless, and the gene is clustered with genes KCNA1 and KCNA6 on chromosome 12. Defects in this gene are a cause of familial atrial fibrillation type 7 (ATFB7). [provided by RefSeq, May 2012]

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• BS2: High AC in GnomAdExome4 at 16 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNA5	NM_002234.4	c.1354G>C	p.Val452Leu	missense_variant	Exon 1 of 1	ENST00000252321.5	NP_002225.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNA5	ENST00000252321.5	c.1354G>C	p.Val452Leu	missense_variant	Exon 1 of 1	6	NM_002234.4	ENSP00000252321.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251476 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135918

Gnomad AFR exome AF: 0.00

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000109 AC: 16 AN: 1461892 Hom.: 0 Cov.: 34 AF XY: 0.0000110 AC XY: 8 AN XY: 727248

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: 0.0000144

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.000111 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Atrial fibrillation, familial, 7 Uncertain:1

Jun 23, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine with leucine at codon 452 of the KCNA5 protein (p.Val452Leu). The valine residue is highly conserved and there is a small physicochemical difference between valine and leucine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with KCNA5-related disease. 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"). 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. -

not provided Uncertain:1

Aug 19, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.77	D
Eigen	Uncertain	0.40
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.97	D
M_CAP	Uncertain	0.24	D
MetaRNN	Uncertain	0.67	D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Uncertain	2.2	M
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-2.8	D
REVEL	Pathogenic	0.67
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.019	D
Polyphen		1.0	D
Vest4		0.55
MutPred		0.46		Loss of catalytic residue at V452 (P = 0.075);
MVP		1.0
MPC		1.4
ClinPred		0.96	D
GERP RS		3.1
Varity_R		0.69
gMVP		0.90

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: rs1486417435; hg19: chr12-5154667;