chr1-45331492-G-A

Position:

• chr1-45331492-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6 BP7

The NM_001048174.2(MUTYH):​c.1167C>T​(p.Arg389=) variant causes a synonymous 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. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: MUTYH NM_001048174.2 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: 0.483

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]

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant 1-45331492-G-A is Benign according to our data. Variant chr1-45331492-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 185395.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=1}.
• BP7: Synonymous conserved (PhyloP=0.483 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MUTYH	NM_001128425.2	c.1251C>T	p.Arg417=	synonymous_variant	13/16	ENST00000710952.2	NP_001121897.1
MUTYH	NM_001048174.2	c.1167C>T	p.Arg389=	synonymous_variant	13/16	ENST00000456914.7	NP_001041639.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MUTYH	ENST00000710952.2	c.1251C>T	p.Arg417=	synonymous_variant	13/16		NM_001128425.2	ENSP00000518552
MUTYH	ENST00000456914.7	c.1167C>T	p.Arg389=	synonymous_variant	13/16	1	NM_001048174.2	ENSP00000407590	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 03, 2014	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Feb 01, 2018	- -

Familial adenomatous polyposis 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 19, 2016

In summary, this is a rare silent change with uncertain impact on splicing. It has been classified as a Variant of Uncertain Significance. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MUTYH-related disease. ClinVar contains an entry for this variant (Variation ID: 185395). Algorithms developed to predict the effect of sequence changes on mRNA splicing suggest that this variant may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. This sequence change affects codon 417 of the MUTYH mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the MUTYH protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	1.6
DANN	Benign	0.74
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
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: rs786202141; hg19: chr1-45797164;