3-37048562-C-T

Position:

chr3-37048562-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2PM5PP3_StrongPP5_Very_Strong

The NM_000249.4(MLH1):c.1942C>T(p.Pro648Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,676 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P648L) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

Clinical Significance

Pathogenic reviewed by expert panel P:8

Conservation

PhyloP100: 7.59

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:

MLH1 (HGNC:):

MLH1 links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr3-37048563-C-T is described in Lovd as [Pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.969

PP5

Variant 3-37048562-C-T is Pathogenic according to our data. Variant chr3-37048562-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 17097.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr3-37048562-C-T is described in Lovd as [Pathogenic]. Variant chr3-37048562-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MLH1	NM_000249.4 linkuse as main transcript	c.1942C>T	p.Pro648Ser	missense_variant	17/19	ENST00000231790.8	NP_000240.1	P40692-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MLH1	ENST00000231790.8 linkuse as main transcript	c.1942C>T	p.Pro648Ser	missense_variant	17/19	1	NM_000249.4	ENSP00000231790.3		P40692-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1461676

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727158

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:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8

Revision: reviewed by expert panel

LINK: link

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 2

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 02, 2024	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 01, 2004	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Jul 24, 2023	This variant is considered likely pathogenic. This variant is strongly associated with more severe personal and family histories of cancer, typical for individuals with pathogenic variants in this gene [PMID: 27363726]. -

Lynch syndrome

Pathogenic:1

Pathogenic, reviewed by expert panel

research

International Society for Gastrointestinal Hereditary Tumours (InSiGHT)

Sep 05, 2013

Multifactorial likelihood analysis posterior probability >0.99 -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Dec 27, 2019

Not found in the total gnomAD dataset, and the data is high quality. Found in at least one patient with expected phenotype for this gene. Predicted to have a damaging effect on the protein. Located in potentially critical domain of the protein. Assessment of experimental evidence suggests this variant results in abnormal protein function. Segregation with disease in affected individuals -

Hereditary nonpolyposis colorectal neoplasms

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 21, 2023

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 648 of the MLH1 protein (p.Pro648Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with Lynch Syndrome (PMID: 12112654, 15139004, 16724012). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 17097). 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 expected to disrupt MLH1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects MLH1 function (PMID: 15139004, 16724012, 21404117). This variant disrupts the p.Pro648 amino acid residue in MLH1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11726306, 16083711, 21404117). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 28, 2018

The p.P648S pathogenic mutation (also known as c.1942C>T), located in coding exon 17 of the MLH1 gene, results from a C to T substitution at nucleotide position 1942. The proline at codon 648 is replaced by serine, an amino acid with similar properties. This mutation has been reported in multiple individuals satisfying clinical diagnostic criteria for HNPCC/Lynch syndrome (Bisgaard et al. Hum Mut 2002 Jul; 20(1): 20-7; Raevaara et al. Genes Chromosomes Cancer 2004 Jul; 40(3): 261-5; Belvederesi et al. Eur J Hum Genet 2006 Jul; 14(7): 853 9; Ou et al. Hum Mut 2007 Nov; 28(11): 104754). Tumor studies in some of these individuals demonstrated microsatellite instability and loss of MLH1 protein expression on immunohistochemistry. In addition, this mutation has been shown to disrupt interaction between MLH1 and PMS2 in vitro (Belvederesi et al. Eur J Hum Genet 2006 Jul; 14(7): 853-9). This alteration has been classified as pathogenic using the following lines of evidence: in silico prediction models, segregation with disease, clinical phenotype including tumor characteristics, mutation co-occurrence, and functional studies (Thompson BA et al. Hum. Mutat. 2013 Jan;34:200-9; Thompson BA et al. Nat. Genet. 2014 Feb;46:107-15; available at [www.insight-group.org/variants/classifications/]). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Mismatch repair cancer syndrome 1

Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jul 01, 2004

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.92

BayesDel_addAF

Pathogenic

0.50

BayesDel_noAF

Pathogenic

0.49

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.95

D;.;.;.;.;.

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.97

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.93

D;D;.;.;.;D

M_CAP

Pathogenic

0.49

MetaRNN

Pathogenic

0.97

D;D;D;D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.8

H;.;.;.;.;.

PrimateAI

Uncertain

0.65

PROVEAN

Pathogenic

-7.7

D;D;D;D;D;D

REVEL

Pathogenic

0.94

Sift

Pathogenic

0.0

D;D;D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;D;D;D

Polyphen

1.0

D;.;.;.;.;.

Vest4

0.91

MutPred

0.85

Loss of catalytic residue at P648 (P = 0.0446);.;.;.;.;.;

MVP

0.94

MPC

0.41

ClinPred

1.0

GERP RS

5.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.95

gMVP

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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