rs876657408

Variant names:

• chr5-112775623-AAAT-A
• rs876657408
• NM_000038.6:c.423-4_423-2delATA

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000038.6(APC):​c.423-4_423-2delATA variant causes a splice acceptor, splice region, intron change. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: APC NM_000038.6 splice_acceptor, splice_region, intron
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 4.78
• Publications: 0 publications found

Genes affected

APC (HGNC:583): (APC regulator of WNT signaling pathway) This gene encodes a tumor suppressor protein that acts as an antagonist of the Wnt signaling pathway. It is also involved in other processes including cell migration and adhesion, transcriptional activation, and apoptosis. Defects in this gene cause familial adenomatous polyposis (FAP), an autosomal dominant pre-malignant disease that usually progresses to malignancy. Mutations in the APC gene have been found to occur in most colorectal cancers, where disease-associated mutations tend to be clustered in a small region designated the mutation cluster region (MCR) and result in a truncated protein product. [provided by RefSeq, Jun 2022]

APC Gene-Disease associations (from GenCC):

• classic or attenuated familial adenomatous polyposis

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• desmoid tumor

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp
• familial adenomatous polyposis 1

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
• gastric adenocarcinoma and proximal polyposis of the stomach

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
• sarcoma

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• APC-related attenuated familial adenomatous polyposis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Turcot syndrome with polyposis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Cenani-Lenz syndactyly syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 1.2, offset of -37, new splice context is: tcttctgcagtctttattAGcat. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000038.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APC	NM_000038.6	MANE Select	c.423-4_423-2delATA		splice_acceptor splice_region intron	N/A	NP_000029.2
	APC	NM_001407446.1		c.453-4_453-2delATA		splice_acceptor splice_region intron	N/A	NP_001394375.1
	APC	NM_001354896.2		c.423-4_423-2delATA		splice_acceptor splice_region intron	N/A	NP_001341825.1	R4GMU6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APC	ENST00000257430.9	TSL:5 MANE Select	c.423-5_423-3delAAT		splice_region intron	N/A	ENSP00000257430.4	P25054-1
	APC	ENST00000508376.6	TSL:1	c.423-5_423-3delAAT		splice_region intron	N/A	ENSP00000427089.2	P25054-1
	APC	ENST00000502371.3	TSL:1	n.423-5_423-3delAAT		splice_region intron	N/A	ENSP00000484935.2	A0A087X2F3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1429670 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 712388

African (AFR) AF: 0.00 AC: 0 AN: 32472

American (AMR) AF: 0.00 AC: 0 AN: 43556

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25750

East Asian (EAS) AF: 0.00 AC: 0 AN: 39320

South Asian (SAS) AF: 0.00 AC: 0 AN: 82552

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53234

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5338

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1088320

Other (OTH) AF: 0.00 AC: 0 AN: 59128

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	Familial adenomatous polyposis 1 (2)
-	1	-	Hereditary cancer-predisposing syndrome (1)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		4.8
Mutation Taster		=1/99	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs876657408; hg19: chr5-112111320;