16-68813496-G-C

Position:

• chr16-68813496-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2_Supporting PS4_Supporting PVS1_Strong PM5_Supporting PS3_Supporting

This summary comes from the ClinGen Evidence Repository: The c.1320+1G>C variant occurs at the canonical splice donor site of exon 9 (PVS1_strong, PM5_supporting). This variant is absent from populations in gnomAD (PM2_supporting; http://gnomad.broadinstitute.org). Splicing analysis in vitro has shown that the C allele results in skipping of exon 9, producing an abnormal in-frame transcript (PS3_supporting; PMID:8033105, 28301459). Furthermore, this variant has been observed in at least one family meeting IGCLC criteria for HDGC (PS4_supporting; SCV000322628.7). In summary, this variant meets criteria to be classified as likely pathogenic based on the ACMG/AMP criteria applied as specified by the CDH1 Variant Curation Expert Panel (Variant Interpretation Guidelines Version 3.1): PVS1_strong, PM2_supporting, PS3_supporting, PS4_supporting, PM5_supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA10588622/MONDO:0007648/007

• Frequency: Genomes: not found (cov: 32)
• Consequence: CDH1 NM_004360.5 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic reviewed by expert panel P:4
• Conservation: PhyloP100: 8.51

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PS4: 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CDH1	NM_004360.5	c.1320+1G>C		splice_donor_variant		ENST00000261769.10	NP_004351.1
CDH1	NM_001317186.2	c.-500+1G>C		splice_donor_variant			NP_001304115.1
CDH1	NM_001317185.2	c.-295G>C		5_prime_UTR_variant	9/16		NP_001304114.1
CDH1	NM_001317184.2	c.1137+1233G>C		intron_variant			NP_001304113.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDH1	ENST00000261769.10	c.1320+1G>C		splice_donor_variant		1	NM_004360.5	ENSP00000261769	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:4

Revision: reviewed by expert panel

Submissions by phenotype

Blepharocheilodontic syndrome 1 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Sep 20, 2017

- -

Hereditary diffuse gastric adenocarcinoma Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Jun 28, 2023

This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

May 15, 2017

This variant is denoted CDH1 c.1320+1G>C or IVS9+1G>C and consists of a G>C nucleotide substitution at the +1 position of intron 9 of the CDH1 gene. This variant destroys a canonical splice donor site and has been shown to result in in-frame skipping of exon 9 (Becker 1994). Even though this variant results in an in-frame transcript, this single exon deletion would result in the loss of 61 residues, which are located within the cadherin 3 domain (UniProt). Based on the currently available information, we consider CDH1 c.1320+1G>C to be pathogenic. -

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

Likely pathogenic, reviewed by expert panel

curation

ClinGen CDH1 Variant Curation Expert Panel

Aug 24, 2023

The c.1320+1G>C variant occurs at the canonical splice donor site of exon 9 (PVS1_strong, PM5_supporting). This variant is absent from populations in gnomAD (PM2_supporting; http://gnomad.broadinstitute.org). Splicing analysis in vitro has shown that the C allele results in skipping of exon 9, producing an abnormal in-frame transcript (PS3_supporting; PMID: 8033105, 28301459). Furthermore, this variant has been observed in at least one family meeting IGCLC criteria for HDGC (PS4_supporting; SCV000322628.7). In summary, this variant meets criteria to be classified as likely pathogenic based on the ACMG/AMP criteria applied as specified by the CDH1 Variant Curation Expert Panel (Variant Interpretation Guidelines Version 3.1): PVS1_strong, PM2_supporting, PS3_supporting, PS4_supporting, PM5_supporting. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.29		Position offset: 8
DS_DL_spliceai		1.0		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs886039685; hg19: chr16-68847399; COSMIC: COSV55740321; COSMIC: COSV55740321;