rs1553125786

chr1-45331481-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001048174.2(MUTYH):c.1178T>C(p.Leu393Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L393L) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: MUTYH NM_001048174.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.78

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_pathogenic. Variant got 6 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 16 uncertain in NM_001048174.2
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.862

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MUTYH	NM_001128425.2	c.1262T>C	p.Leu421Pro	missense_variant	13/16	ENST00000710952.2
MUTYH	NM_001048174.2	c.1178T>C	p.Leu393Pro	missense_variant	13/16	ENST00000456914.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MUTYH	ENST00000710952.2	c.1262T>C	p.Leu421Pro	missense_variant	13/16		NM_001128425.2
MUTYH	ENST00000456914.7	c.1178T>C	p.Leu393Pro	missense_variant	13/16	1	NM_001048174.2	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial adenomatous polyposis 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 02, 2021

This sequence change replaces leucine with proline at codon 421 of the MUTYH protein (p.Leu421Pro). The leucine residue is moderately conserved and there is a moderate physicochemical difference between leucine and proline. This variant is not present in population databases (ExAC 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: 464682). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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 v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.43
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.040
Cadd	Benign	21
Dann	Uncertain	0.98
Eigen	Benign	0.088
Eigen_PC	Benign	0.050
FATHMM_MKL	Benign	0.19	N
M_CAP	Uncertain	0.16	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.20	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Benign	0.45	T
PROVEAN	Uncertain	-2.6	D;N;N;N;N;N;N;N;N;D;N;.
REVEL	Uncertain	0.40
Sift	Benign	0.031	D;T;T;T;T;T;T;T;T;D;T;.
Sift4G	Uncertain	0.036	D;T;T;T;T;T;T;T;T;D;T;T
Polyphen		0.44, 0.74, 0.62	.;.;.;.;.;.;B;P;.;.;P;.
Vest4		0.74
MutPred		0.77		.;.;.;.;.;.;.;.;.;.;Gain of disorder (P = 0.0138);.;
MVP		0.84
MPC		0.62
ClinPred		0.91	D
GERP RS		4.2
Varity_R		0.76
gMVP		0.81

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: rs1553125786; hg19: chr1-45797153;