16-68813493-A-G

Position:

• chr16-68813493-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PM5

The NM_004360.5(CDH1):​c.1318A>G​(p.Lys440Glu) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000263 in 152,206 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. K440N) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.000026 (0 hom., cov: 32)
• Consequence: CDH1 NM_004360.5 missense, splice_region
• Scores: Splicing: ADA: 0.6958
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 6.15

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-68813495-G-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CDH1	NM_004360.5	c.1318A>G	p.Lys440Glu	missense_variant, splice_region_variant	9/16	ENST00000261769.10	NP_004351.1
CDH1	NM_001317185.2	c.-298A>G		5_prime_UTR_variant	9/16		NP_001304114.1
CDH1	NM_001317186.2	c.-502A>G		splice_region_variant, 5_prime_UTR_variant	9/15		NP_001304115.1
CDH1	NM_001317184.2	c.1137+1230A>G		intron_variant			NP_001304113.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDH1	ENST00000261769.10	c.1318A>G	p.Lys440Glu	missense_variant, splice_region_variant	9/16	1	NM_004360.5	ENSP00000261769	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152206 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251472 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135912

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 32

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152206 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74356

Gnomad4 AFR AF: 0.0000965

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000658 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Feb 06, 2023

- -

CDH1-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Sep 21, 2022

The CDH1 c.1318A>G variant is predicted to result in the amino acid substitution p.Lys440Glu. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.012% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/16-68847396-A-G) and is reported as a variant of uncertain significance in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/231836/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Hereditary diffuse gastric adenocarcinoma Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 24, 2023

This sequence change replaces lysine, which is basic and polar, with glutamic acid, which is acidic and polar, at codon 440 of the CDH1 protein (p.Lys440Glu). This variant is present in population databases (rs778212100, gnomAD 0.01%). 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: 231836). 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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 20, 2022

The p.K440E variant (also known as c.1318A>G), located in coding exon 9 of the CDH1 gene, results from an A to G substitution at nucleotide position 1318. The lysine at codon 440 is replaced by glutamic acid, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. 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	Benign	0.15
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Pathogenic	0.18
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.51	D;T;T;.
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.80	T;T;T;T
M_CAP	Benign	0.078	D
MetaRNN	Uncertain	0.55	D;D;D;D
MetaSVM	Uncertain	-0.19	T
MutationAssessor	Pathogenic	3.0	M;.;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-3.6	D;.;.;.
REVEL	Uncertain	0.63
Sift	Uncertain	0.0070	D;.;.;.
Sift4G	Uncertain	0.011	D;D;D;D
Polyphen		0.98	D;.;.;.
Vest4		0.79
MVP		0.89
MPC		1.1
ClinPred		0.90	D
GERP RS		5.8
Varity_R		0.57
gMVP		0.87

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.70
dbscSNV1_RF	Benign	0.47
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs778212100; hg19: chr16-68847396;