rs1555515297

Variant names:

• chr16-68808850-T-C
• rs1555515297
• NM_004360.5:c.687+2T>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM5_Supporting PM2_Supporting PVS1_Strong BS2_Supporting

This summary comes from the ClinGen Evidence Repository: The c.687+2T>C variant is a canonical splice variant predicted to result in a truncated or absent protein (PVS1_Strong, PM5_Supporting). The variant is absent in the gnomAD cohort (PM2_Supporting; http://gnomad.broadinstitute.org). This variant is at +2 donor site variant with other likely pathogenic canonical splicing variants curated at the same splice site (PM5_Supporting). The variant has been observed in 6 individuals without DGC, SRC tumors or LBC and whose families do not suggest HDGC (BS2_Supporting). In summary, the clinical significance of this variant is uncertain. ACMG/AMP criteria applied, as specified by the CDH1 Variant Curation Expert Panel (Variant Interpretation Guidelines Version 3.1): PVS1_Strong, PM2_Supporting, PM5_Supporting, BS2_Supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA396458165/MONDO:0007648/007

• Frequency: Genomes: not found (cov: 32)
• Consequence: CDH1 NM_004360.5 splice_donor, intron
• Scores: Splicing: ADA: 0.9845
• Clinical Significance: Uncertain significance reviewed by expert panel P:2 U:1
• Conservation: PhyloP100: 7.46
• Publications: 0 publications found

Genes affected

CDH1 (HGNC:1748): (cadherin 1) This gene encodes a classical cadherin of the cadherin superfamily. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate the mature glycoprotein. This calcium-dependent cell-cell adhesion protein is comprised of five extracellular cadherin repeats, a transmembrane region and a highly conserved cytoplasmic tail. Mutations in this gene are correlated with gastric, breast, colorectal, thyroid and ovarian cancer. Loss of function of this gene is thought to contribute to cancer progression by increasing proliferation, invasion, and/or metastasis. The ectodomain of this protein mediates bacterial adhesion to mammalian cells and the cytoplasmic domain is required for internalization. This gene is present in a gene cluster with other members of the cadherin family on chromosome 16. [provided by RefSeq, Nov 2015]

CDH1 Gene-Disease associations (from GenCC):

• blepharocheilodontic syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Illumina, Labcorp Genetics (formerly Invitae), G2P
• CDH1-related diffuse gastric and lobular breast cancer syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P
• hereditary breast carcinoma

  Inheritance: AD Classification: DEFINITIVE Submitted by: Ambry Genetics
• hereditary diffuse gastric adenocarcinoma

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
• cleft soft palate

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• orofacial cleft 3

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• blepharocheilodontic syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial ovarian cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM5: For more information check the summary or visit ClinGen Evidence Repository.
• BS2: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDH1	NM_004360.5	c.687+2T>C		splice_donor_variant, intron_variant	Intron 5 of 15	ENST00000261769.10	NP_004351.1
CDH1	NM_001317184.2	c.687+2T>C		splice_donor_variant, intron_variant	Intron 5 of 14		NP_001304113.1
CDH1	NM_001317185.2	c.-929+2T>C		splice_donor_variant, intron_variant	Intron 5 of 15		NP_001304114.1
CDH1	NM_001317186.2	c.-1133+2T>C		splice_donor_variant, intron_variant	Intron 5 of 14		NP_001304115.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDH1	ENST00000261769.10	c.687+2T>C		splice_donor_variant, intron_variant	Intron 5 of 15	1	NM_004360.5	ENSP00000261769.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:2 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Hereditary diffuse gastric adenocarcinoma Pathogenic:1

Oct 28, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. For these reasons, this variant has been classified as Pathogenic. This sequence change affects a donor splice site in intron 5 of the CDH1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CDH1 are known to be pathogenic (PMID: 15235021, 20373070). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individuals with diffuse gastric cancer (PMID: 15235021; Invitae). ClinVar contains an entry for this variant (Variation ID: 463790). -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jan 07, 2019

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.687+2T>C intronic variant results from a T to C substitution two nucleotides after coding exon 5 in the CDH1 gene. This nucleotide position is highly conserved in available vertebrate species. Using the ESEfinder and HSF splice site prediction tools, this alteration is predicted to abolish the native splice donor site; however, direct evidence is unavailable. Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -

CDH1-related diffuse gastric and lobular breast cancer syndrome Uncertain:1

Feb 26, 2024

ClinGen CDH1 Variant Curation Expert Panel

Significance: Uncertain significance

Review Status: reviewed by expert panel

Collection Method: curation

The c.687+2T>C variant is a canonical splice variant predicted to result in a truncated or absent protein (PVS1_Strong, PM5_Supporting). The variant is absent in the gnomAD cohort (PM2_Supporting; http://gnomad.broadinstitute.org). This variant is at +2 donor site variant with other likely pathogenic canonical splicing variants curated at the same splice site (PM5_Supporting). The variant has been observed in 6 individuals without DGC, SRC tumors or LBC and whose families do not suggest HDGC (BS2_Supporting). In summary, the clinical significance of this variant is uncertain. ACMG/AMP criteria applied, as specified by the CDH1 Variant Curation Expert Panel (Variant Interpretation Guidelines Version 3.1): PVS1_Strong, PM2_Supporting, PM5_Supporting, BS2_Supporting. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Pathogenic	29
DANN	Uncertain	0.98
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		7.5
GERP RS		5.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Benign	0.67
SpliceAI score (max)		0.54		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.54		Position offset: -44

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1555515297; hg19: chr16-68842753;