NM_004655.4:c.1637delG

Variant names:

• chr17-65537398-GC-G
• rs1555577625
• NM_004655.4:c.1637delG

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_004655.4(AXIN2):​c.1637delG​(p.Gly546AlafsTer143) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G546G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: AXIN2 NM_004655.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.46
• Publications: 0 publications found

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]

AXIN2 Gene-Disease associations (from GenCC):

• oligodontia-cancer predisposition syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• tooth agenesis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• craniosynostosis

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-65537398-GC-G is Pathogenic according to our data. Variant chr17-65537398-GC-G is described in ClinVar as [Pathogenic]. Clinvar id is 464561.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AXIN2	NM_004655.4	c.1637delG	p.Gly546AlafsTer143	frameshift_variant	Exon 6 of 11	ENST00000307078.10	NP_004646.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AXIN2	ENST00000307078.10	c.1637delG	p.Gly546AlafsTer143	frameshift_variant	Exon 6 of 11	1	NM_004655.4	ENSP00000302625.5
AXIN2	ENST00000375702.5	c.1637delG	p.Gly546AlafsTer78	frameshift_variant	Exon 5 of 9	1		ENSP00000364854.5
AXIN2	ENST00000618960.4	c.1637delG	p.Gly546AlafsTer78	frameshift_variant	Exon 6 of 10	5		ENSP00000478916.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Oligodontia-cancer predisposition syndrome Pathogenic:1

Oct 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gly546Alafs*143) in the AXIN2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in AXIN2 are known to be pathogenic (PMID: 15042511, 21416598). 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: 464561). For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jan 17, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1637delG pathogenic mutation, located in coding exon 5 of the AXIN2 gene, results from a deletion of one nucleotide at nucleotide position 1637, causing a translational frameshift with a predicted alternate stop codon (p.G546Afs*143). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.5
Mutation Taster		=7/193	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1555577625; hg19: chr17-63533516; COSMIC: COSV61061278;