Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate
The NM_001148.6(ANK2):c.2108C>T(p.Ala703Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,908 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).
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]
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 703 of the ANK2 protein (p.Ala703Val). This variant is present in population databases (rs756016862, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with ANK2-related conditions. ClinVar contains an entry for this variant (Variation ID: 578200). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt ANK2 protein function. 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. -
Cardiovascular phenotype Uncertain:1
Nov 17, 2023
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The p.A703V variant (also known as c.2108C>T), located in coding exon 19 of the ANK2 gene, results from a C to T substitution at nucleotide position 2108. The alanine at codon 703 is replaced by valine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -