16-68833284-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_004360.5(CDH1):c.2440-6C>T variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CDH1 NM_004360.5 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.00002972
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: -0.395

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_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).
• BP6: Variant 16-68833284-C-T is Benign according to our data. Variant chr16-68833284-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 414040.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CDH1	NM_004360.5	c.2440-6C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000261769.10
CDH1	NM_001317184.2	c.2257-6C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant
CDH1	NM_001317185.2	c.892-6C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant
CDH1	NM_001317186.2	c.475-6C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CDH1	ENST00000261769.10	c.2440-6C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_004360.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

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

Apr 23, 2020

Variant summary: CDH1 c.2440-6C>T alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251368 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.2440-6C>T in individuals affected with Breast Cancer and no experimental evidence demonstrating its impact on protein function have been reported. A ClinVar submitter (evaluation after 2014) cites the variant as likely benign. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary diffuse gastric adenocarcinoma Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jul 16, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
Cadd	Benign	3.2
Dann	Benign	0.40

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000030
dbscSNV1_RF	Benign	0.0
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

Publications

LitVar

Other links and lift over

dbSNP: rs139757930; hg19: chr16-68867187;