3-37028863-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 0P and 0B.

The NM_000249.4(MLH1):c.1489C>T(p.Arg497Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000929 in 1,614,130 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1O:1

Conservation

PhyloP100: 0.676

Variant links:

Genes affected

MLH1 (HGNC:7127): (mutL homolog 1) The protein encoded by this gene can heterodimerize with mismatch repair endonuclease PMS2 to form MutL alpha, part of the DNA mismatch repair system. When MutL alpha is bound by MutS beta and some accessory proteins, the PMS2 subunit of MutL alpha introduces a single-strand break near DNA mismatches, providing an entry point for exonuclease degradation. The encoded protein is also involved in DNA damage signaling and can heterodimerize with DNA mismatch repair protein MLH3 to form MutL gamma, which is involved in meiosis. This gene was identified as a locus frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). [provided by RefSeq, Aug 2017]

MLH1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH1	NM_000249.4 link	c.1489C>T	p.Arg497Trp	missense_variant	Exon 13 of 19	ENST00000231790.8	NP_000240.1	P40692-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MLH1	ENST00000231790.8 link	c.1489C>T	p.Arg497Trp	missense_variant	Exon 13 of 19	1	NM_000249.4	ENSP00000231790.3		P40692-1

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152168

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000145

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

GnomAD3 exomes

AF:

0.0000239

AC:

AN:

251486

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135912

show subpopulations

Gnomad AFR exome

AF:

0.000185

Gnomad AMR exome

AF:

0.0000289

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:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000547

AC:

AN:

1461844

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727228

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

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:

0.00000450

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000460

AC:

AN:

152286

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.000144

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000850

Hom.:

Bravo

AF:

0.0000264

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Feb 17, 2023	This missense variant replaces arginine with tryptophan at codon 497 of the MLH1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with MLH1-related disorders in the literature. This variant has been identified in 9/282892 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	May 10, 2024	The p.R497W variant (also known as c.1489C>T), located in coding exon 13 of the MLH1 gene, results from a C to T substitution at nucleotide position 1489. The arginine at codon 497 is replaced by tryptophan, an amino acid with dissimilar properties. This variant was identified in a cohort of 3,579 African males diagnosed with prostate cancer who underwent multi-gene panel testing of 19 DNA repair and cancer predisposition genes (Matejcic M et al. JCO Precis Oncol, 2020 Jan;4:32-43).This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Nov 18, 2021	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jan 11, 2017	This variant is denoted MLH1 c.1489C>T at the cDNA level, p.Arg497Trp (R497W) at the protein level, and results in the change of an Arginine to a Tryptophan (CGG>TGG). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. MLH1 Arg497Trp was not observed at a significant allele frequency in 1000 Genomes. Since Arginine and Tryptophan differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. MLH1 Arg497Trp occurs at a position where amino acids with properties similar to Arginine are tolerated across species and is located in the PMS2/PMS1 interaction domain and region of interaction with EXO1 (Pang 1997, UniProt). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available evidence, it is unclear whether MLH1 Arg497Trp is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Nov 01, 2016	Variant summary: The MLH1 c.1489C>T (p.Arg497Trp) variant causes a missense change involving a non-conserved nucleotide with 3/4 in silico tools (SNPs&Go not captured here due to low reliability index) predict a "benign" outcome, although these predictions have yet to be functionally assessed. The variant of interest was observed in the large, broad control population, ExAC, with an allele frequency of 3/121412 (1/40469), which does not exceed the estimated maximal expected allele frequency for a pathogenic MLH1 variant of 1/1407. The variant of interest has not, to our knowledge, been reported in affected individuals via publications, however, multiple clinical diagnostic laboratories cite the variant as "uncertain significance." Therefore, until additional information becomes available (ie, clinical and functional studies), the variant of interest has been classified as a "Variant of Uncertain Significance (VUS)." -

Colorectal cancer, hereditary nonpolyposis, type 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Dec 14, 2023

- -

Lynch syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Mar 24, 2024

This missense variant replaces arginine with tryptophan at codon 497 of the MLH1 protein. Computational prediction tools and conservation analyses are inconclusive regarding the impact of this variant on the protein function. Computational splicing tools suggest that this variant may not impact RNA splicing. To our knowledge, functional assays have not been performed for this variant nor has this variant been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 9/282892 chromosomes in the general population by the Genome Aggregation Database (gnomAD). 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. -

Hereditary nonpolyposis colorectal neoplasms

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 22, 2024

- -

Colorectal cancer, hereditary nonpolyposis, type 2;C5399763:Mismatch repair cancer syndrome 1

Other:1

not provided, no classification provided

phenotyping only

GenomeConnect - Invitae Patient Insights Network

Variant interpreted as Uncertain significance and reported on 10-30-2018 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.15

BayesDel_addAF

Uncertain

0.059

BayesDel_noAF

Uncertain

0.13

CADD

Uncertain

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.72

D;.;.;.;.;.;T;T

Eigen

Uncertain

0.36

Eigen_PC

Uncertain

0.25

FATHMM_MKL

Benign

0.25

LIST_S2

Uncertain

0.92

D;D;.;.;.;D;D;D

M_CAP

Uncertain

0.25

MetaRNN

Uncertain

0.54

D;D;D;D;D;D;D;D

MetaSVM

Uncertain

0.44

MutationAssessor

Uncertain

2.5

M;.;.;.;.;.;.;.

PrimateAI

Uncertain

0.57

PROVEAN

Uncertain

-3.9

D;D;D;D;D;D;D;D

REVEL

Uncertain

0.59

Sift

Uncertain

0.0020

D;D;D;D;D;D;D;D

Sift4G

Uncertain

0.0050

D;D;D;D;D;D;D;D

Polyphen

1.0

D;.;.;.;.;.;.;.

Vest4

0.67

MVP

0.90

MPC

0.37

ClinPred

0.90

GERP RS

4.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.57

gMVP

0.44

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over