rs558707786

chr1-45333507-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PM5 PP5

The NM_001048174.2(MUTYH):c.170A>G(p.His57Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,614,182 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H57Y) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MUTYH NM_001048174.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:4
• Conservation: PhyloP100: 6.63

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 Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-45333508-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1703759.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP5: Variant 1-45333507-T-C is Pathogenic according to our data. Variant chr1-45333507-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 234004.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=3, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MUTYH	NM_001128425.2	c.254A>G	p.His85Arg	missense_variant	3/16	ENST00000710952.2
MUTYH	NM_001048174.2	c.170A>G	p.His57Arg	missense_variant	3/16	ENST00000456914.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MUTYH	ENST00000710952.2	c.254A>G	p.His85Arg	missense_variant	3/16		NM_001128425.2
MUTYH	ENST00000456914.7	c.170A>G	p.His57Arg	missense_variant	3/16	1	NM_001048174.2	A1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152178 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.00316

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251476 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135912

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461886 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152296 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74468

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 30, 2016	This variant is denoted MUTYH c.254A>G at the cDNA level, p.His85Arg (H85R) at the protein level, and results in the change of a Histidine to an Arginine (CAT>CGT). This variant was observed in the homozygous state in a patient who had a history of 10-100 colorectal adenomas and a sibling with colorectal cancer (Morak 2010). MUTYH His85Arg was not observed at a significant frequency in large population cohorts (NHLBI Exome Sequencing Project, The 1000 Genomes Consortium 2015, Lek 2016). Since Histidine and Arginine share similar properties, this is considered a conservative amino acid substitution. MUTYH His85Arg occurs at a position that is conserved across species and is not located in a known functional domain. In silico analyses predict that this variant is probably damaging to protein structure and function. Based on the currently available evidence and internal data, we consider MUTYH His85Arg to be a likely pathogenic variant. Of note, MUTYH-Associated Polyposis (MAP) is a recessive condition associated with two pathogenic variants on opposite chromosomes in MUTYH. -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 10, 2023	The frequency of this variant in the general population, 0.000008 (2/251476 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in an individual with MUTYH-Associated Polyposis (PMID: 30604180 (2019)). Additionally, the variant was reported in a family with a history of polyps and colorectal cancer (PMID: 20618354 (2010)). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded conflicting predictions that this variant is deleterious or benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 20, 2023	The p.H85R variant (also known as c.254A>G), located in coding exon 3 of the MUTYH gene, results from an A to G substitution at nucleotide position 254. The histidine at codon 85 is replaced by arginine, an amino acid with highly similar properties. This variant has been identified in the homozygous state and likely in trans with a MUTYH pathogenic variant in individuals diagnosed with clinical features of MUTYH-associated polyposis (MAP) (Morak M et al. Clin Genet, 2010 Oct;78:353-63; Interlaboratory communication). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 06, 2020	This missense variant replaces histidine with arginine at codon 85 of the MUTYH protein. This variant is also known as c.212A>G (p.His71Arg) based on an alternative transcript (NM_001048171). Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in the homozygous state in an individual affected with colon adenomas (PMID: 20618354). This variant has also been identified in 2/251476 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Familial adenomatous polyposis 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Aug 07, 2023

ClinVar contains an entry for this variant (Variation ID: 234004). For these reasons, this variant has been classified as Pathogenic. 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 disruptive. This missense change has been observed in individuals with colorectal polyposis (PMID: 20618354; Invitae). It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs558707786, gnomAD 0.007%). This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 85 of the MUTYH protein (p.His85Arg). -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Apr 16, 2021

Variant summary: MUTYH c.254A>G (p.His85Arg) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251476 control chromosomes. c.254A>G has been reported in the literature in one homozygous individual affected with 10-100 colorectal adenomas and a sibling affected with colorectal cancer (Morak_2010). Additionally, the variant was also reported in one individual with MUTYH-Associated Polyposis (Sutcliffe_2019). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance (n=3) and likely pathogenic (n=1). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Carcinoma of colon Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The MUTYH p.His85Arg variant was not identified in the literature nor was it identified in the following databases: Cosmic, MutDB, Insight Colon Cancer Gene Variant Database. The variant was identified in dbSNP (ID: rs558707786) as “With Uncertain significance allele”,ClinVar (1x as uncertain significance by Ambry Genetics), and Clinvitae (1x as uncertain significance). The variant was identified in control databases in 2 of 246258 chromosomes at a frequency of 0.000008 in the following populations: African in 1 of 15304 chromosomes (freq. 0.000065), and Other in 1 of 5486 chromosomes (freq. 0.00018) (Genome Aggregation Consortium Feb 27, 2017). The p.His85Arg residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and 1 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Pathogenic	0.26
Cadd	Uncertain	24
Dann	Uncertain	1.0
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	1.0	D
M_CAP	Benign	0.026	D
MetaRNN	Uncertain	0.70	D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.43	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.58	T
PROVEAN	Pathogenic	-4.9	D;D;D;D;D;D;D;D;D;D;D;D
REVEL	Uncertain	0.43
Sift	Uncertain	0.0020	D;D;D;D;D;D;D;D;D;D;D;D
Sift4G	Benign	0.12	T;D;T;T;T;D;T;T;T;D;T;D
Polyphen		0.99, 0.97, 0.34	.;.;.;.;.;D;D;.;B;.;.;.
Vest4		0.70
MutPred		0.54		.;.;.;.;.;.;.;.;Gain of MoRF binding (P = 0.0134);.;.;.;
MVP		0.90
MPC		0.55
ClinPred		0.93	D
GERP RS		5.9
Varity_R		0.83
gMVP		0.74

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs558707786; hg19: chr1-45799179;