rs1555583424

chr17-65558124-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004655.4(AXIN2):c.497T>C(p.Ile166Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I166L) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: AXIN2 NM_004655.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.19

Genes affected

AXIN2 (HGNC:904): (axin 2) The Axin-related protein, Axin2, presumably plays an important role in the regulation of the stability of beta-catenin in the Wnt signaling pathway, like its rodent homologs, mouse conductin/rat axil. In mouse, conductin organizes a multiprotein complex of APC (adenomatous polyposis of the colon), beta-catenin, glycogen synthase kinase 3-beta, and conductin, which leads to the degradation of beta-catenin. Apparently, the deregulation of beta-catenin is an important event in the genesis of a number of malignancies. The AXIN2 gene has been mapped to 17q23-q24, a region that shows frequent loss of heterozygosity in breast cancer, neuroblastoma, and other tumors. Mutations in this gene have been associated with colorectal cancer with defective mismatch repair. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.745

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AXIN2	NM_004655.4	c.497T>C	p.Ile166Thr	missense_variant	2/11	ENST00000307078.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AXIN2	ENST00000307078.10	c.497T>C	p.Ile166Thr	missense_variant	2/11	1	NM_004655.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Oligodontia-cancer predisposition syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 05, 2021

This sequence change replaces isoleucine with threonine at codon 166 of the AXIN2 protein (p.Ile166Thr). The isoleucine residue is highly conserved and there is a moderate physicochemical difference between isoleucine and threonine. 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. 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 disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with AXIN2-related disease. This variant is not present in population databases (ExAC no frequency). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 06, 2023

The p.I166T variant (also known as c.497T>C), located in coding exon 1 of the AXIN2 gene, results from a T to C substitution at nucleotide position 497. The isoleucine at codon 166 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
Cadd	Pathogenic	27
Dann	Benign	0.93
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Uncertain	0.97	D
M_CAP	Benign	0.030	D
MetaRNN	Pathogenic	0.74	D;D;D;D;D;D
MetaSVM	Benign	-0.94	T
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Uncertain	-3.8	D;.;D;.;.;.
REVEL	Uncertain	0.52
Sift	Uncertain	0.0020	D;.;D;.;.;.
Sift4G	Uncertain	0.0080	D;D;D;.;.;.
Polyphen		0.99	.;D;D;.;.;.
Vest4		0.75
MutPred		0.48		Loss of stability (P = 0.0123);Loss of stability (P = 0.0123);Loss of stability (P = 0.0123);Loss of stability (P = 0.0123);Loss of stability (P = 0.0123);Loss of stability (P = 0.0123);
MVP		0.45
MPC		0.79
ClinPred		0.97	D
GERP RS		4.6
gMVP		0.60

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: rs1555583424; hg19: chr17-63554242;