NM_000038.6:c.2834_2835delGGinsTT

Variant names:

• chr5-112838428-GG-TT
• rs786204162
• NM_000038.6:c.2834_2835delGGinsTT

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_000038.6(APC):​c.2834_2835delGGinsTT​(p.Arg945Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. The variant is present in control chromosomes in GnomAd MNV project. The variant allele was found at a frequency of 0.0000354 in 10 alleles, including 0 homozygotes. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R945S) has been classified as Uncertain significance.

• Frequency: GnomAD MNV: 𝑓 0.000035 Genomes: not found (cov: 32)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7 B:1
• Conservation: PhyloP100: 9.60
• Publications: 2 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: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
• 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

ENSG00000258864 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APC	NM_000038.6	MANE Select	c.2834_2835delGGinsTT	p.Arg945Ile	missense	N/A	NP_000029.2
	APC	NM_001407446.1		c.2918_2919delGGinsTT	p.Arg973Ile	missense	N/A	NP_001394375.1
	APC	NM_001354896.2		c.2888_2889delGGinsTT	p.Arg963Ile	missense	N/A	NP_001341825.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APC	ENST00000257430.9	TSL:5 MANE Select	c.2834_2835delGGinsTT	p.Arg945Ile	missense	N/A	ENSP00000257430.4
	APC	ENST00000508376.6	TSL:1	c.2834_2835delGGinsTT	p.Arg945Ile	missense	N/A	ENSP00000427089.2
	APC	ENST00000502371.3	TSL:1	n.*1032_*1033delGGinsTT		non_coding_transcript_exon	Exon 12 of 12	ENSP00000484935.2

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

GnomAD MNV AF: 0.0000354 AC: 10 Hom.: 0

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	3	-	not provided (3)
-	2	-	Familial adenomatous polyposis 1 (2)
-	1	1	Hereditary cancer-predisposing syndrome (2)
-	1	-	Desmoid disease, hereditary (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.6

Splicing

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

Other links and lift over

dbSNP: rs786204162; hg19: chr5-112174125;