3-37042330-C-T

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP6

The NM_000249.4(MLH1):c.1730C>T(p.Ser577Leu) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000194 in 1,598,554 control chromosomes in the GnomAD database, including 1 homozygotes. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. S577S) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000019 ( 1 hom. )

Consequence

MLH1
NM_000249.4 missense, splice_region

Scores

Splicing: ADA: 0.9898

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:11B:4O:1

Conservation

PhyloP100: 7.06

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 Likely_benign. Variant got -1 ACMG points.

BP6

Variant 3-37042330-C-T is Benign according to our data. Variant chr3-37042330-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 127619.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=11, Benign=2, Likely_benign=2, not_provided=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH1	NM_000249.4 link	c.1730C>T	p.Ser577Leu	missense_variant, splice_region_variant	Exon 15 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.1730C>T	p.Ser577Leu	missense_variant, splice_region_variant	Exon 15 of 19	1	NM_000249.4	ENSP00000231790.3		P40692-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152110

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:

0.000193

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000597

AC:

AN:

251202

Hom.:

AF XY:

0.0000589

AC XY:

AN XY:

135766

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000707

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000187

AC:

AN:

1446444

Hom.:

Cov.:

AF XY:

0.0000180

AC XY:

AN XY:

720782

show subpopulations

Gnomad4 AFR exome

AF:

0.0000603

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000252

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000118

Gnomad4 OTH exome

AF:

0.0000167

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152110

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74304

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000115

Hom.:

Bravo

AF:

0.0000945

ExAC

AF:

0.0000577

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:11Benign:4Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 2

Uncertain:4Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Jun 23, 2016	- -
Uncertain significance, criteria provided, single submitter	clinical testing	St. Jude Molecular Pathology, St. Jude Children's Research Hospital	May 22, 2024	The MLH1 c.1730C>T (p.Ser577Leu) missense change has a maximum subpopulation frequency of 0.07% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant has been reported in individuals with Lynch syndrome-associated tumors (PMID: 27601186; 28767289). In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
Likely benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 14, 2023	This variant is considered likely benign. This variant is strongly associated with less severe personal and family histories of cancer, typical for individuals without pathogenic variants in this gene [PMID: 25085752]. -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 27, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Apr 27, 2017	This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not provided

Uncertain:2Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 13, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jun 01, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Feb 03, 2023	Observed in individuals with a personal or family history of Lynch syndrome-associated cancers and in a healthy individual undergoing whole genome sequencing (Chao et al., 2008; Bodian et al., 2014; Lagerstedt-Robinson et al., 2016; Shindo et al., 2017); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; In silico analysis is inconclusive as to whether the variant alters gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; Also known as c.1007C>T; p.(Ser336Leu); This variant is associated with the following publications: (PMID: 33471991, 25186627), 30982232, 32914570, 31391288, 24728327, 27601186, 18383312, 28767289, 33281875, 32959997, 27535533, 12799449, 20533529, 22753075) -

not specified

Uncertain:2Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	May 06, 2015	- -
not provided, no classification provided	reference population	ITMI	Sep 19, 2013	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 06, 2022	Variant summary: MLH1 c.1730C>T (p.Ser577Leu) results in a non-conservative amino acid change located in the C-terminal domain (IPR032189) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 6e-05 in 251202 control chromosomes, predominantly at a frequency of 0.00071 within the East Asian subpopulation in the gnomAD database, including 1 homozygote.The variant, c.1730C>T, has been reported in the literature in individuals affected with colorectal cancer and other tumor phenotypes that belong to the Lynch Syndrome tumor spectrum (example: Chao_2008, Lagerstedt-Robinson_2016, Toh_2018, Li_2020, Jiang_2020, Shindo_2017 etc.). However, these reports do not provide unequivocal conclusions about association of the variant with Lynch Syndrome. The variant has been also reported in the literature in multiple individuals affected with Breast Cancer (example: Tung_2015, Wang_2019 etc.). However, a recent large-scale Breast Cancer study reported the variant in 13/60466 BrC cases and 13/53461 controls, i.e. with a calculated odds ratio of 0.88, which suggests that this variant is not associated with a risk for Breast Cancer (Dorling_2021). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Ten clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar and classified the variant as VUS (n=8), likely benign (n=1) or benign (n=1). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Hereditary cancer-predisposing syndrome

Uncertain:1Benign:1

Benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 08, 2020	This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 20, 2023	This missense variant replaces serine with leucine at codon 577 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 been observed in individuals affected with Lynch syndrome, breast, and pancreatic cancer (PMID: 25186627, 27601186, 28767289, 31360874, 32659497, 32914570, 32959997, 33471991), as well as in multiple unaffected individuals reported in pancreatic cancer and breast cancer case-control studies (PMID: 32980694, 33471991). This variant has been identified in 17/282594 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. -

Muir-Torré syndrome;C1333991:Colorectal cancer, hereditary nonpolyposis, type 2;C5399763:Mismatch repair cancer syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

May 23, 2017

- -

Lynch syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jul 10, 2024

This missense variant replaces serine with leucine at codon 577 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 been observed in individuals affected with Lynch syndrome, breast and pancreatic cancer (PMID: 25186627, 27601186, 28767289, 31360874, 32659497, 32914570, 32959997) and an unaffected individual in a pancreatic cancer case-control study (PMID: 32980694). However, this variant has not shown a significant association with breast cancer in a large case-control study, with an odds ratio reported at 0.884 (95% confidence interval: 0.41 to 1.907, PMID: 33471991). This variant has been identified in 17/282594 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. -

Hereditary nonpolyposis colorectal neoplasms

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 02, 2025

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.27

BayesDel_addAF

Pathogenic

0.21

BayesDel_noAF

Pathogenic

0.42

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.87

D;.;.;.;.;.

Eigen

Uncertain

0.43

Eigen_PC

Uncertain

0.52

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.97

D;D;.;.;.;D

M_CAP

Uncertain

0.21

MetaRNN

Uncertain

0.68

D;D;D;D;D;D

MetaSVM

Uncertain

0.47

MutationAssessor

Pathogenic

3.3

M;.;.;.;.;.

PrimateAI

Uncertain

0.67

PROVEAN

Pathogenic

-4.6

D;D;D;D;D;D

REVEL

Pathogenic

0.67

Sift

Uncertain

0.0080

D;D;D;D;D;D

Sift4G

Uncertain

0.017

D;D;D;D;D;D

Polyphen

0.30

B;.;.;.;.;.

Vest4

0.77

MVP

0.97

MPC

0.13

ClinPred

0.68

GERP RS

5.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.7

Varity_R

0.74

gMVP

0.71

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

0.99

dbscSNV1_RF

Pathogenic

0.88

SpliceAI score (max)

0.23

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.23

Position offset: 1

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