1-45331466-C-G

Variant names:

• chr1-45331466-C-G
• rs748700385
• NM_001048174.2:c.1193G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_001048174.2(MUTYH):​c.1193G>C​(p.Arg398Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,864 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R398H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MUTYH NM_001048174.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -1.13
• Publications: 11 publications found

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]

MUTYH Gene-Disease associations (from GenCC):

• familial adenomatous polyposis 2

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen, G2P
• colorectal cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• familial ovarian cancer

  Inheritance: AD, AR Classification: NO_KNOWN Submitted by: ClinGen
• hereditary breast carcinoma

  Inheritance: AD, AR Classification: NO_KNOWN Submitted by: ClinGen

ENSG00000288208 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 16 benign, 56 uncertain in NM_001048174.2
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2584157).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MUTYH	NM_001048174.2	c.1193G>C	p.Arg398Pro	missense_variant	Exon 13 of 16	ENST00000456914.7	NP_001041639.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MUTYH	ENST00000456914.7	c.1193G>C	p.Arg398Pro	missense_variant	Exon 13 of 16	1	NM_001048174.2	ENSP00000407590.2
ENSG00000288208	ENST00000671898.1	n.1781G>C		non_coding_transcript_exon_variant	Exon 17 of 21			ENSP00000499896.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461864 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727234

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53398

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 2 Uncertain:1

Oct 09, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 426 of the MUTYH protein (p.Arg426Pro). 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. ClinVar contains an entry for this variant (Variation ID: 186486). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Hereditary cancer-predisposing syndrome Uncertain:1

May 13, 2017

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R426P variant (also known as c.1277G>C), located in coding exon 13 of the MUTYH gene, results from a G to C substitution at nucleotide position 1277. The arginine at codon 426 is replaced by proline, an amino acid with dissimilar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of p.R426P remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Uncertain	0.055	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	2.3
DANN	Benign	0.88
DEOGEN2	Benign	0.41	.;.;.;.;.;.;T;.;.;.;.;T
Eigen	Benign	-0.94
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.031	N
LIST_S2	Benign	0.58	.;.;T;.;T;T;T;T;T;T;T;T
M_CAP	Benign	0.045	D
MetaRNN	Benign	0.26	T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.98	T
MutationAssessor	Benign	1.5	.;.;.;.;.;.;L;.;.;.;.;.
PhyloP100		-1.1
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-2.0	N;N;N;N;N;N;N;N;N;N;N;.
REVEL	Uncertain	0.56
Sift	Benign	0.086	T;T;T;T;T;T;D;T;T;T;D;.
Sift4G	Benign	0.16	T;T;T;T;T;T;T;T;T;T;T;T
Polyphen		0.0010, 0.21, 0.033	.;.;.;.;.;.;B;B;.;.;B;.
Vest4		0.27
MutPred		0.65		.;.;.;.;.;.;.;.;.;.;Gain of catalytic residue at W427 (P = 0.0258);.;
MVP		0.79
MPC		0.20
ClinPred		0.46	T
GERP RS		-7.4
Varity_R		0.63
gMVP		0.74
Mutation Taster		=73/27	polymorphism

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

Other links and lift over

dbSNP: rs748700385; hg19: chr1-45797138;