chr3-37047562-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_000249.4(MLH1):​c.1775G>C​(p.Ser592Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000682 in 1,614,028 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S592G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

1
11
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:12B:2

Conservation

PhyloP100: 3.76

Publications

8 publications found
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 Gene-Disease associations (from GenCC):
  • Lynch syndrome
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
  • Lynch syndrome 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp
  • Muir-Torre syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Orphanet
  • mismatch repair cancer syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
  • Lynch syndrome 1
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • ovarian cancer
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • malignant pancreatic neoplasm
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • rhabdomyosarcoma
    Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
  • prostate cancer
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • breast cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
  • hereditary breast carcinoma
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 45 uncertain in NM_000249.4

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000249.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MLH1
NM_000249.4
MANE Select
c.1775G>Cp.Ser592Thr
missense
Exon 16 of 19NP_000240.1
MLH1
NM_001354628.2
c.1775G>Cp.Ser592Thr
missense
Exon 16 of 18NP_001341557.1
MLH1
NM_001354629.2
c.1676G>Cp.Ser559Thr
missense
Exon 15 of 18NP_001341558.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MLH1
ENST00000231790.8
TSL:1 MANE Select
c.1775G>Cp.Ser592Thr
missense
Exon 16 of 19ENSP00000231790.3
MLH1
ENST00000456676.7
TSL:1
c.1775G>Cp.Ser592Thr
missense
Exon 16 of 17ENSP00000416687.3
MLH1
ENST00000458205.6
TSL:1
c.1052G>Cp.Ser351Thr
missense
Exon 17 of 20ENSP00000402667.2

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152166
Hom.:
0
Cov.:
31
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251258
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000547
AC:
8
AN:
1461862
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000719
AC:
8
AN:
1111992
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152166
Hom.:
0
Cov.:
31
AF XY:
0.0000269
AC XY:
2
AN XY:
74342
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000675
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:12Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:3
Jan 08, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces serine with threonine at codon 592 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 an individual affected with pancreatic cancer, who also carried an unspecified CDKN2A variant (PMID: 27449771), as well as in an individual affected with prostate cancer (PMID: 29368341). This variant has been identified in 3/251258 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.

Jul 18, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.S592T variant (also known as c.1775G>C), located in coding exon 16 of the MLH1 gene, results from a G to C substitution at nucleotide position 1775. The serine at codon 592 is replaced by threonine, an amino acid with similar properties. This alteration was identified in 1/150 unselected individuals with recurrent or metastatic prostate cancer (Isaacsson Velho P et al. Prostate. 2018 04;78:401-407). This amino acid position is not 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.

Sep 21, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:2Benign:1
Oct 16, 2023
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nov 26, 2024
Myriad Genetics, Inc.
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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: 27363726].

Aug 01, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

Lynch syndrome Uncertain:2
Nov 20, 2015
Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dec 15, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces serine with threonine at codon 592 of the MLH1 protein. Computational prediction tool 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 observed in an individual affected with pancreatic cancer who also has an unspecified CDKN2A variant (PMID: 27449771). This variant has been identified in 3/251258 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 provided Uncertain:2
Apr 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

MLH1: PM2, PS4:Supporting, BP4

Jun 24, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in an individual with prostate cancer, in an individual with pancreatic cancer and a pathogenic CDKN2A variant, as well as in a patient with Li-Fraumeni syndrome and a pathogenic variant in TP53 (PMID: 27449771, 29368341, 37840845); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; In silico analysis suggests this variant may impact gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; This variant is associated with the following publications: (PMID: 30113427, 29368341, 27449771, 12799449, 20533529, 22753075, 37840845)

not specified Uncertain:1
Mar 04, 2025
Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Muir-Torré syndrome;C1333991:Colorectal cancer, hereditary nonpolyposis, type 2;C5399763:Mismatch repair cancer syndrome 1 Uncertain:1
Mar 21, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

MLH1-related disorder Uncertain:1
Jun 14, 2023
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The MLH1 c.1775G>C variant is predicted to result in the amino acid substitution p.Ser592Thr. This variant has been reported in an individual with pancreatic cancer and an individual with prostate cancer (Table S4, Yang et al. 2016, PubMed ID: 27449771; Table S1, Isaacsson Velho et al. 2018. PubMed ID: 29368341). This variant is reported in 3 of ~251,000 alleles in gnomAD (http://gnomad.broadinstitute.org/variant/3-37089053-G-C). It is interpreted as uncertain significance in ClinVar (https://preview.ncbi.nlm.nih.gov/clinvar/variation/142658/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Hereditary nonpolyposis colorectal neoplasms Benign:1
Jan 28, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.092
BayesDel_addAF
Pathogenic
0.18
D
BayesDel_noAF
Uncertain
0.090
CADD
Uncertain
25
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.73
D
Eigen
Uncertain
0.36
Eigen_PC
Uncertain
0.42
FATHMM_MKL
Uncertain
0.85
D
LIST_S2
Uncertain
0.90
D
M_CAP
Benign
0.029
D
MetaRNN
Uncertain
0.57
D
MetaSVM
Benign
-0.74
T
MutationAssessor
Uncertain
2.0
M
PhyloP100
3.8
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-1.5
N
REVEL
Uncertain
0.57
Sift
Benign
0.23
T
Sift4G
Benign
0.42
T
Polyphen
0.062
B
Vest4
0.54
MVP
0.94
MPC
0.063
ClinPred
0.48
T
GERP RS
4.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.25
gMVP
0.53
Mutation Taster
=88/12
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.34
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.34
Position offset: -3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs587782621; hg19: chr3-37089053; API