4-113292418-C-G

Position:

• chr4-113292418-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_001148.6(ANK2):​c.2280C>G​(p.Asn760Lys) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,456,752 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. N760N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: ANK2 NM_001148.6 missense, splice_region
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: -0.508

Genes affected

ANK2 (HGNC:493): (ankyrin 2) This gene encodes a member of the ankyrin family of proteins that link the integral membrane proteins to the underlying spectrin-actin cytoskeleton. Ankyrins play key roles in activities such as cell motility, activation, proliferation, contact and the maintenance of specialized membrane domains. Most ankyrins are typically composed of three structural domains: an amino-terminal domain containing multiple ankyrin repeats; a central region with a highly conserved spectrin binding domain; and a carboxy-terminal regulatory domain which is the least conserved and subject to variation. The protein encoded by this gene is required for targeting and stability of Na/Ca exchanger 1 in cardiomyocytes. Mutations in this gene cause long QT syndrome 4 and cardiac arrhythmia syndrome. Multiple transcript variants encoding different isoforms have been described. [provided by RefSeq, Dec 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 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), ANK2. . Gene score misZ 1.9641 (greater than the threshold 3.09). Trascript score misZ 4.2513 (greater than threshold 3.09). GenCC has associacion of gene with heart conduction disease, Brugada syndrome, long QT syndrome, complex neurodevelopmental disorder, cardiac arrhythmia, ankyrin-B-related, catecholaminergic polymorphic ventricular tachycardia.
• BP4: Computational evidence support a benign effect (MetaRNN=0.22331804).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ANK2	NM_001148.6	c.2280C>G	p.Asn760Lys	missense_variant, splice_region_variant	21/46	ENST00000357077.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ANK2	ENST00000357077.9	c.2280C>G	p.Asn760Lys	missense_variant, splice_region_variant	21/46	1	NM_001148.6	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1456752 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 724214

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000226

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, no assertion criteria provided

provider interpretation

Stanford Center for Inherited Cardiovascular Disease, Stanford University

Mar 07, 2017

- -

Long QT syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 12, 2018

In summary, this variant is a novel missense change with uncertain impact on protein function and mRNA splicing. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with an ANK2-related disease. This sequence change replaces asparagine with lysine at codon 760 of the ANK2 protein (p.Asn760Lys). The asparagine residue is moderately conserved and there is a moderate physicochemical difference between asparagine and lysine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.42
CADD	Benign	18
DANN	Benign	0.86
DEOGEN2	Benign	0.28	.;T;.;T;.;T;T;T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.61	D
LIST_S2	Uncertain	0.91	D;D;D;D;D;D;D;D
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.22	T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.52	T
MutationAssessor	Benign	1.5	.;.;.;.;L;L;.;.
MutationTaster	Benign	0.99	D;D;D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-5.0	D;D;D;D;D;D;D;.
REVEL	Benign	0.27
Sift	Benign	0.92	T;T;T;T;T;D;D;.
Sift4G	Benign	0.29	T;T;T;T;T;D;D;T
Polyphen		0.15, 1.0, 0.99	.;.;B;.;D;D;.;.
Vest4		0.52, 0.47, 0.49, 0.46
MutPred		0.33		.;.;.;.;Gain of MoRF binding (P = 0.0305);Gain of MoRF binding (P = 0.0305);Gain of MoRF binding (P = 0.0305);.;
MVP		0.63
MPC		1.2
ClinPred		0.81	D
GERP RS		-7.5
Varity_R		0.58
gMVP		0.56

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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: rs1060501162; hg19: chr4-114213574;