chr1-45332661-C-A

Variant names:

• chr1-45332661-C-A
• rs1172521297
• NM_001128425.2:c.603G>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1 PM2 BP4 BP6

The NM_001128425.2(MUTYH):​c.603G>T​(p.Met201Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000657 in 152,136 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 Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M201V) has been classified as Likely benign.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: MUTYH NM_001128425.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1
• Conservation: PhyloP100: 3.83
• Publications: 3 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 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 59 uncertain in NM_001128425.2
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.27029663).
• BP6: Variant 1-45332661-C-A is Benign according to our data. Variant chr1-45332661-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 481789.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001128425.2. 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
	MUTYH	NM_001128425.2	MANE Plus Clinical	c.603G>T	p.Met201Ile	missense	Exon 8 of 16	NP_001121897.1
	MUTYH	NM_001048174.2	MANE Select	c.519G>T	p.Met173Ile	missense	Exon 8 of 16	NP_001041639.1
	MUTYH	NM_012222.3		c.594G>T	p.Met198Ile	missense	Exon 8 of 16	NP_036354.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MUTYH	ENST00000710952.2	MANE Plus Clinical	c.603G>T	p.Met201Ile	missense	Exon 8 of 16	ENSP00000518552.2
	MUTYH	ENST00000456914.7	TSL:1 MANE Select	c.519G>T	p.Met173Ile	missense	Exon 8 of 16	ENSP00000407590.2
	MUTYH	ENST00000372098.7	TSL:1	c.594G>T	p.Met198Ile	missense	Exon 8 of 16	ENSP00000361170.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152136 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 36

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152136 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74314

African (AFR) AF: 0.00 AC: 0 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67998

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Sep 09, 2025

Ambry Genetics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as 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.

Feb 27, 2019

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not provided Uncertain:1

Sep 26, 2023

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Familial adenomatous polyposis 2 Uncertain:1

Apr 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 201 of the MUTYH protein (p.Met201Ile). 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: 481789). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The isoleucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Uncertain	0.012	T
BayesDel_noAF	Benign	-0.22
CADD	Benign	23
DANN	Benign	0.96
DEOGEN2	Benign	0.088	T
Eigen	Benign	-0.29
Eigen_PC	Benign	-0.083
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D
M_CAP	Benign	0.047	D
MetaRNN	Benign	0.27	T
MetaSVM	Benign	-0.37	T
MutationAssessor	Benign	-0.79	N
PhyloP100		3.8
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-1.2	N
REVEL	Benign	0.26
Sift	Benign	0.41	T
Sift4G	Benign	0.43	T
Polyphen		0.0020	B
Vest4		0.36
MutPred		0.53		Gain of catalytic residue at M201 (P = 0.0037)
MVP		0.88
MPC		0.14
ClinPred		0.45	T
GERP RS		3.3
PromoterAI		-0.0097	Neutral
Varity_R		0.25
gMVP		0.63
Mutation Taster		=71/29	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs1172521297; hg19: chr1-45798333;