chr16-68828275-G-C

Variant names:

• chr16-68828275-G-C
• rs1555517677
• NM_004360.5:c.2266G>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_004360.5(CDH1):​c.2266G>C​(p.Asp756His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,842 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D756E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CDH1 NM_004360.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.16
• 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 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 14 uncertain in NM_004360.5
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDH1	NM_004360.5	c.2266G>C	p.Asp756His	missense_variant	Exon 14 of 16	ENST00000261769.10	NP_004351.1
CDH1	NM_001317184.2	c.2083G>C	p.Asp695His	missense_variant	Exon 13 of 15		NP_001304113.1
CDH1	NM_001317185.2	c.718G>C	p.Asp240His	missense_variant	Exon 14 of 16		NP_001304114.1
CDH1	NM_001317186.2	c.301G>C	p.Asp101His	missense_variant	Exon 13 of 15		NP_001304115.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDH1	ENST00000261769.10	c.2266G>C	p.Asp756His	missense_variant	Exon 14 of 16	1	NM_004360.5	ENSP00000261769.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461842 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727214

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111984

Other (OTH) AF: 0.00 AC: 0 AN: 60394

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.029673), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary diffuse gastric adenocarcinoma Uncertain:1

Oct 05, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with histidine, which is basic and polar, at codon 756 of the CDH1 protein (p.Asp756His). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CDH1-related conditions. ClinVar contains an entry for this variant (Variation ID: 532464). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Oct 19, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D756H variant (also known as c.2266G>C), located in coding exon 14 of the CDH1 gene, results from a G to C substitution at nucleotide position 2266. The aspartic acid at codon 756 is replaced by histidine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious 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	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.51	D;T;.
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D;D
M_CAP	Uncertain	0.091	D
MetaRNN	Uncertain	0.61	D;D;D
MetaSVM	Uncertain	0.27	D
MutationAssessor	Pathogenic	3.2	M;.;.
PhyloP100		8.2
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-5.5	D;.;D
REVEL	Pathogenic	0.74
Sift	Uncertain	0.0030	D;.;D
Sift4G	Uncertain	0.0050	D;D;D
Polyphen		1.0	D;.;.
Vest4		0.64
MutPred		0.67		Loss of loop (P = 0.0804);.;.;
MVP		0.96
MPC		0.99
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.87
gMVP		0.81
Mutation Taster		=44/56	disease causing

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: rs1555517677; hg19: chr16-68862178;