rs587779959

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM1

The NM_000249.4(MLH1):c.945C>G(p.His315Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,614,106 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H315D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:11

Conservation

PhyloP100: 1.41

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 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 2 benign, 15 uncertain in NM_000249.4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MLH1	NM_000249.4 linkuse as main transcript	c.945C>G	p.His315Gln	missense_variant	11/19	ENST00000231790.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MLH1	ENST00000231790.8 linkuse as main transcript	c.945C>G	p.His315Gln	missense_variant	11/19	1	NM_000249.4	P1	P40692-1

Frequencies

GnomAD3 genomes

AF:

0.0000328

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

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:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251402

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135868

show subpopulations

Gnomad AFR exome

AF:

0.00

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:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000150

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000165

AC XY:

AN XY:

727244

show subpopulations

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:

0.0000198

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000328

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74374

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000735

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000151

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:11

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Sep 13, 2023	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26845104, 25503501, 22753075, 28259476, 32547938) -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Nov 01, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jul 27, 2020	- -

Colorectal cancer, hereditary nonpolyposis, type 2

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 08, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Jun 04, 2019	- -

Lynch syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Nov 20, 2023	This missense variant replaces histidine with glutamine at codon 315 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). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 25503501), as well as in an individual with family history of colon and pancreatic cancer (PMID: 26845104). This variant has been identified in 5/282808 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	University of Washington Department of Laboratory Medicine, University of Washington	Nov 20, 2015	- -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 23, 2024	The p.H315Q variant (also known as c.945C>G), located in coding exon 11 of the MLH1 gene, results from a C to G substitution at nucleotide position 945. The histidine at codon 315 is replaced by glutamine, an amino acid with highly similar properties. This alteration was previously reported in at least one individual from a cohort of 278 BRCA1/2-negative individuals with early-onset breast cancer via multiplex panel testing of 22 cancer susceptibility genes. (Maxwell KN et al. Genet. Med., 2015 Aug;17:630-8). In a cohort of 1462 individuals referred to the University of Washington for their BROCA or ColoSeq multigene panel testing, this alteration was detected in an individual with colon polyps and a family history of colon and pancreatic cancer, and is classified by the authors as a variant of uncertain significance (Shirts BH et al. Genet. Med. 2016 Oct;18(10):974-81). This alteration was also observed in an individual with metastatic castration-resistant prostate cancer (Annala M et al. Eur. Urol., 2017 07;72:34-42). In another study, this alteration was identified in 1/711 breast cancer patients and 0/492 healthy controls (Nikitin AG et al. Front Oncol. 2020 May;10:666). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 17, 2023	This missense variant replaces histidine with glutamine at codon 315 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 performed for this variant. This variant has been reported in individuals affected with breast cancer (PMID: 25503501, 32547938), prostate cancer (PMID: 28259476), as well as in an individual affected with colon polyps with family history of colon and pancreatic cancer (PMID: 26845104). This variant has been identified in 5/282808 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. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Jul 26, 2021

Variant summary: MLH1 c.945C>G (p.His315Gln) results in a non-conservative amino acid change located in the DNA mismatch repair protein family, N-terminal domain (IPR002099) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.6e-05 in 251402 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.945C>G has been reported in the literature as a VUS in settings of multigene cancer panel testing in cohorts of individuals with a family/personal history of cancer (example, Shirts_2015), breast cancer (example, Maxwell_2015, Nikitin_2020) and metastatic castration-resistant prostate cancer (mCRPC) (example, Annala_2017). These report(s) do not provide unequivocal conclusions about association of the variant with Lynch Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary nonpolyposis colorectal neoplasms

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 09, 2023

This sequence change replaces histidine, which is basic and polar, with glutamine, which is neutral and polar, at codon 315 of the MLH1 protein (p.His315Gln). This variant is present in population databases (rs587779959, gnomAD 0.004%). This missense change has been observed in individual(s) with breast cancer, colon polyps and prostate cancer (PMID: 25503501, 26845104, 28259476, 32547938). ClinVar contains an entry for this variant (Variation ID: 127623). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MLH1 protein function with a negative predictive value of 95%. 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

0.51

BayesDel_addAF

Pathogenic

0.24

BayesDel_noAF

Pathogenic

0.21

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.74

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

Eigen

Uncertain

0.32

Eigen_PC

Uncertain

0.38

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.96

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

M_CAP

Benign

0.037

MetaRNN

Uncertain

0.69

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

MetaSVM

Benign

-0.75

MutationAssessor

Uncertain

2.1

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

MutationTaster

Benign

1.0

D;D;D;D;D;D

PrimateAI

Pathogenic

0.80

PROVEAN

Pathogenic

-4.9

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

REVEL

Uncertain

0.61

Sift

Benign

0.087

T;T;T;T;T;T;T

Sift4G

Benign

0.15

T;T;T;T;T;T;T

Polyphen

0.94

P;.;.;.;.;.;.

Vest4

0.81

MutPred

0.61

Gain of ubiquitination at K311 (P = 0.0817);.;.;.;.;.;.;

MVP

0.92

MPC

0.33

ClinPred

0.75

GERP RS

5.2

Varity_R

0.54

gMVP

0.61

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