chr1-45329403-CT-C

Position:

• chr1-45329403-CT-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_001048174.2(MUTYH):​c.1468delA​(p.Ser490fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: MUTYH NM_001048174.2 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.358

Genes affected

MUTYH (HGNC:7527): (mutY DNA glycosylase) This gene encodes a DNA glycosylase involved in oxidative DNA damage repair. The enzyme excises adenine bases from the DNA backbone at sites where adenine is inappropriately paired with guanine, cytosine, or 8-oxo-7,8-dihydroguanine, a major oxidatively damaged DNA lesion. The protein is localized to the nucleus and mitochondria. This gene product is thought to play a role in signaling apoptosis by the introduction of single-strand breaks following oxidative damage. Mutations in this gene result in heritable predisposition to colorectal cancer, termed MUTYH-associated polyposis (MAP). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2017]

ENSG00000288208 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0626 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-45329403-CT-C is Pathogenic according to our data. Variant chr1-45329403-CT-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 238341.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MUTYH	NM_001048174.2	c.1468delA	p.Ser490fs	frameshift_variant	16/16	ENST00000456914.7	NP_001041639.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MUTYH	ENST00000456914.7	c.1468delA	p.Ser490fs	frameshift_variant	16/16	1	NM_001048174.2	ENSP00000407590.2
ENSG00000288208	ENST00000671898.1	n.*211delA		non_coding_transcript_exon_variant	21/21			ENSP00000499896.1
ENSG00000288208	ENST00000671898	n.*211delA		3_prime_UTR_variant	15/15			ENSP00000499896.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial adenomatous polyposis 2 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 08, 2023

This sequence change creates a premature translational stop signal (p.Ser518Valfs*53) in the MUTYH gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 32 amino acid(s) of the MUTYH protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MUTYH-related conditions. This variant is also known as Gln512-Phe519. ClinVar contains an entry for this variant (Variation ID: 238341). This variant disrupts the conserved PCNA binding motif of the MUTYH protein, which has been shown to be critical for MUTYH-PCNA binding and repair efficiency (PMID: 11092888, 26377631, 11433026, 11864576). While functional studies have not been performed to directly test the effect of this variant on MUTYH protein function, this suggests that disruption of this region of the protein is causative of disease. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

Publications

LitVar

Other links and lift over

dbSNP: rs878854186; hg19: chr1-45795075;