14-62707524-T-A

Position:

• chr14-62707524-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_139318.5(KCNH5):​c.2951A>T​(p.Asp984Val) variant causes a missense change. The variant allele was found at a frequency of 0.000000772 in 1,294,994 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: 7.7e-7 (0 hom.)
• Consequence: KCNH5 NM_139318.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.04

Genes affected

KCNH5 (HGNC:6254): (potassium voltage-gated channel subfamily H member 5) This gene encodes a member of voltage-gated potassium channels. Members of this family have diverse functions, including regulating neurotransmitter and hormone release, cardiac function, and cell volume. This protein is an outward-rectifying, noninactivating channel. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNH5. . Gene score misZ 2.509 (greater than the threshold 3.09). Trascript score misZ 3.7308 (greater than threshold 3.09). GenCC has associacion of gene with infantile-onset epilepsy.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNH5	NM_139318.5	c.2951A>T	p.Asp984Val	missense_variant	11/11	ENST00000322893.12	NP_647479.2
KCNH5	NM_172375.3	c.*918A>T		3_prime_UTR_variant	10/10		NP_758963.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNH5	ENST00000322893.12	c.2951A>T	p.Asp984Val	missense_variant	11/11	1	NM_139318.5	ENSP00000321427	P1
KCNH5	ENST00000420622.6			downstream_gene_variant		1		ENSP00000395439

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.72e-7 AC: 1 AN: 1294994 Hom.: 0 Cov.: 27 AF XY: 0.00000159 AC XY: 1 AN XY: 628582

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: 9.74e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Early infantile epileptic encephalopathy with suppression bursts Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 02, 2018

This sequence change replaces aspartic acid with valine at codon 984 of the KCNH5 protein (p.Asp984Val). The aspartic acid residue is moderately conserved and there is a large physicochemical difference between aspartic acid and valine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with KCNH5-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.31	T
Eigen	Uncertain	0.36
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.83	T
M_CAP	Pathogenic	0.66	D
MetaRNN	Uncertain	0.47	T
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Benign	1.8	L
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-2.5	N
REVEL	Pathogenic	0.65
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.022	D
Polyphen		0.93	P
Vest4		0.35
MutPred		0.21		Gain of catalytic residue at F988 (P = 0.0197);
MVP		0.73
MPC		0.20
ClinPred		0.92	D
GERP RS		4.3
Varity_R		0.25
gMVP		0.62

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: rs1566633394; hg19: chr14-63174242;