rs1555583178

Positions:

• chr17-65557825-T-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_004655.4(AXIN2):​c.796A>G​(p.Thr266Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar 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:3
• Conservation: PhyloP100: 0.600

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.034180135).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AXIN2	NM_004655.4	c.796A>G	p.Thr266Ala	missense_variant	2/11	ENST00000307078.10	NP_004646.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AXIN2	ENST00000307078.10	c.796A>G	p.Thr266Ala	missense_variant	2/11	1	NM_004655.4	ENSP00000302625	P1
AXIN2	ENST00000375702.5	c.796A>G	p.Thr266Ala	missense_variant	1/9	1		ENSP00000364854
AXIN2	ENST00000618960.4	c.796A>G	p.Thr266Ala	missense_variant	2/10	5		ENSP00000478916
AXIN2	ENST00000577278.1	c.796A>G	p.Thr266Ala	missense_variant	2/2	5		ENSP00000464264

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Oligodontia-cancer predisposition syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 27, 2024

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 266 of the AXIN2 protein (p.Thr266Ala). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with AXIN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 533143). 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 AXIN2 protein function with a negative predictive value of 80%. 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. -

Colorectal cancer Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 21, 2023

- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 31, 2024

The p.T266A variant (also known as c.796A>G), located in coding exon 1 of the AXIN2 gene, results from an A to G substitution at nucleotide position 796. The threonine at codon 266 is replaced by alanine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. 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	Benign	0.063
BayesDel_addAF	Benign	-0.092	T
BayesDel_noAF	Benign	-0.37
CADD	Benign	12
DANN	Benign	0.81
DEOGEN2	Benign	0.23	.;T;T;T
Eigen	Benign	-1.0
Eigen_PC	Benign	-0.94
FATHMM_MKL	Benign	0.093	N
LIST_S2	Benign	0.60	.;T;.;T
M_CAP	Benign	0.028	D
MetaRNN	Benign	0.034	T;T;T;T
MetaSVM	Benign	-0.97	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	0.030	N;.;N;.
REVEL	Benign	0.10
Sift	Benign	0.73	T;.;T;.
Sift4G	Benign	1.0	T;T;T;.
Polyphen		0.0020	.;B;B;.
Vest4		0.020
MutPred		0.15		Loss of phosphorylation at T266 (P = 0.0504);Loss of phosphorylation at T266 (P = 0.0504);Loss of phosphorylation at T266 (P = 0.0504);Loss of phosphorylation at T266 (P = 0.0504);
MVP		0.47
MPC		0.17
ClinPred		0.044	T
GERP RS		1.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
gMVP		0.33

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: rs1555583178; hg19: chr17-63553943;