16-68808692-G-C

Variant names:

• chr16-68808692-G-C
• rs771085839
• NM_004360.5:c.532-1G>C

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM5_Supporting PM2_Supporting PVS1_Strong PS4 PS3

This summary comes from the ClinGen Evidence Repository: The c.532-1G>C variant is a canonical splice variant predicted to result in a truncated or absent protein (PVS1_Strong, PM5_Supporting). This variant is present once (1/245,906 alleles) in the gnomAD v2 cohort (PM2_Supporting; http://gnomad.broadinstitute.org). Additionally, this variant has been reported in six families meeting HDGC clinical criteria (PS4; internal laboratory data). RNA analysis demonstrated that this variant results in an out-of-frame transcript, r.532_547del p.(I178Tfs*32) (PS3; internal laboratory data). In summary, this variant meets criteria to be classified as 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, PS4, PS3, PM5_Supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA8129891/MONDO:0007648/007

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CDH1 NM_004360.5 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic reviewed by expert panel P:9
• Conservation: PhyloP100: 9.60
• Publications: 2 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: Pathogenic. The variant received 14 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 rank	MANE	Protein	UniProt
CDH1	NM_004360.5	c.532-1G>C		splice_acceptor_variant, intron_variant	Intron 4 of 15	ENST00000261769.10	NP_004351.1
CDH1	NM_001317184.2	c.532-1G>C		splice_acceptor_variant, intron_variant	Intron 4 of 14		NP_001304113.1
CDH1	NM_001317185.2	c.-1084-1G>C		splice_acceptor_variant, intron_variant	Intron 4 of 15		NP_001304114.1
CDH1	NM_001317186.2	c.-1288-1G>C		splice_acceptor_variant, intron_variant	Intron 4 of 14		NP_001304115.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDH1	ENST00000261769.10	c.532-1G>C		splice_acceptor_variant, intron_variant	Intron 4 of 15	1	NM_004360.5	ENSP00000261769.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 250964 AF XY: 0.00000737

Gnomad AFR exome AF: 0.0000620

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461816 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727210

African (AFR) AF: 0.0000299 AC: 1 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53376

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111994

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:9

Revision: reviewed by expert panel

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:3

May 31, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant causes a G to C nucleotide substitution at the -1 position of intron 4 of the CDH1 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with esophagogastric cancer in the literature (PMID: 26556299). This variant has been identified in 1/250964 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of CDH1 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Likely Pathogenic. -

Sep 26, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.532-1G>C intronic variant results from a G to C substitution one nucleotide upstream from coding exon 5 of the CDH1 gene. This alteration was observed in 1 of 5054 African American women with breast cancer (Palmer JR et al. J Natl Cancer Inst, 2020 Dec;112:1213-1221). This alteration was also identified in an individual diagnosed with diffuse gastric cancer and colorectal cancer (Adib E et al. Br J Cancer, 2022 Mar;126:797-803). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site and will result in the creation or strengthening of a novel splice acceptor site; however, direct evidence is insufficient at this time (Ambry internal data). 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. -

Oct 22, 2021

Sema4, Sema4

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

- -

not provided Pathogenic:2

Feb 18, 2019

Revvity Omics, Revvity

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 10, 2022

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Canonical splice site variant expected to result in aberrant splicing, although in the absence of functional evidence the actual effect of this sequence change is unknown.; Not observed at significant frequency in large population cohorts (gnomAD); Observed in an individual with breast cancer (Palmer 2020); This variant is associated with the following publications: (PMID: 32427313) -

Hereditary diffuse gastric adenocarcinoma Pathogenic:2

Jun 09, 2023

Myriad Genetics, Inc.

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Apr 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects an acceptor splice site in intron 4 of the CDH1 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs771085839, gnomAD 0.007%). Disruption of this splice site has been observed in individuals with clinical features of hereditary diffuse gastric cancer syndrome (PMID: 26556299; Invitae). ClinVar contains an entry for this variant (Variation ID: 406644). Studies have shown that disruption of this splice site results in partial skipping of exon 5 and introduces a premature termination codon (Invitae). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -

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

Mar 25, 2024

ClinGen CDH1 Variant Curation Expert Panel

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The c.532-1G>C variant is a canonical splice variant predicted to result in a truncated or absent protein (PVS1_Strong, PM5_Supporting). This variant is present once (1/245,906 alleles) in the gnomAD v2 cohort (PM2_Supporting; http://gnomad.broadinstitute.org). Additionally, this variant has been reported in six families meeting HDGC clinical criteria (PS4; internal laboratory data). RNA analysis demonstrated that this variant results in an out-of-frame transcript, r.532_547del p.(I178Tfs*32) (PS3; internal laboratory data). In summary, this variant meets criteria to be classified as 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, PS4, PS3, PM5_Supporting. -

Familial cancer of breast Pathogenic:1

May 15, 2022

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	1.3
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		9.6
GERP RS		5.8
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.98		Position offset: 17
DS_AL_spliceai		0.96		Position offset: 1

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

Other links and lift over

dbSNP: rs771085839; hg19: chr16-68842595; COSMIC: COSV55734907;