rs786202458

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001167617.3(MLH1):​c.-508C>G variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,614,080 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

MLH1
NM_001167617.3 5_prime_UTR_premature_start_codon_gain

Scores

1
18

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:5

Conservation

PhyloP100: -1.48
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.041897535).
BP6
Variant 3-36993556-C-G is Benign according to our data. Variant chr3-36993556-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 185790.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Benign=1, Uncertain_significance=5}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MLH1NM_000249.4 linkc.9C>G p.Phe3Leu missense_variant Exon 1 of 19 ENST00000231790.8 NP_000240.1 P40692-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MLH1ENST00000231790.8 linkc.9C>G p.Phe3Leu missense_variant Exon 1 of 19 1 NM_000249.4 ENSP00000231790.3 P40692-1

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152218
Hom.:
0
Cov.:
33
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:
0.00000398
AC:
1
AN:
251472
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135922
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:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
22
AN:
1461862
Hom.:
0
Cov.:
31
AF XY:
0.0000179
AC XY:
13
AN XY:
727236
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000180
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000328
AC:
5
AN:
152218
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74364
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
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:2
Aug 16, 2021
Genetic Services Laboratory, University of Chicago
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

DNA sequence analysis of the MLH1 gene demonstrated a sequence change, c.9C>G, in exon 1 that results in an amino acid change, p.Phe3Leu. This sequence change has been described in the gnomAD database with frequency of 0.0023% in the non-Finnish European subpopulation (dbSNP rs779759678). The p.Phe3Leu change affects a poorly conserved amino acid residue located in a domain of the MLH1 protein that is not known to be functional. The p.Phe3Leu substitution appears to be benign using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). This sequence change does not appear to have been previously described in individuals with MLH1-related disorders. Due to insufficient evidences and the lack of functional studies, the clinical significance of the p.Phe3Leu change remains unknown at this time. -

Nov 15, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: MLH1 c.9C>G (p.Phe3Leu) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251472 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.9C>G in individuals affected with Hereditary Non-Polyposis Colon Cancer and no experimental evidence demonstrating its impact on protein function have been reported. Four ClinVar submitters (evaluation after 2014) cite the variant as likely benign (n=2) and as uncertain significance (n=2). Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:2
Mar 17, 2022
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter 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.; Not observed in any pancreatic cancer cases but was observed in an unaffected control (Mizukami 2020); This variant is associated with the following publications: (PMID: 22753075, 32980694) -

Nov 01, 2024
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The MLH1 c.9C>G (p.Phe3Leu) variant has been reported in the published literature in reportedly healthy individuals in a large pancreatic cancer study (PMID: 32980694 (2020)) and a biliary tract cancer study (PMID: 36243179 (2022)). In a large scale breast cancer association study, this variant has been observed in one breast cancer case and in one reportedly healthy individual (PMID: 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared)). The frequency of this variant in the general population, 0.000023 (3/129188 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:1Benign:1
Nov 15, 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 12, 2024
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The MLH1 c.9C>G (p.Phe3Leu) missense change has a maximum subpopulation frequency of 0.0023% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL is inconclusive about a pathogenic or benign effect of this variant on protein function, and to our knowledge functional studies have not been performed. To our knowledge, this variant has not been reported in individuals with Lynch syndrome or constitutional mismatch repair deficiency syndrome. 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. -

Hereditary cancer-predisposing syndrome Benign:2
Aug 14, 2017
Color Diagnostics, LLC DBA Color Health
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 02, 2018
Ambry Genetics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This alteration is classified as likely 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. -

Lynch syndrome Benign:1
Oct 06, 2023
All of Us Research Program, National Institutes of Health
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary nonpolyposis colorectal neoplasms Benign:1
Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
-0.023
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
0.017
DANN
Benign
0.82
DEOGEN2
Benign
0.29
T
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.4
FATHMM_MKL
Benign
0.39
N
LIST_S2
Benign
0.60
T
M_CAP
Benign
0.023
T
MetaRNN
Benign
0.042
T
MetaSVM
Benign
-0.80
T
MutationAssessor
Benign
-0.34
N
PrimateAI
Benign
0.45
T
PROVEAN
Benign
0.27
N
REVEL
Uncertain
0.35
Sift
Benign
1.0
T
Sift4G
Benign
1.0
T
Polyphen
0.0
B
Vest4
0.10
MutPred
0.29
Gain of MoRF binding (P = 0.1142);
MVP
0.67
MPC
0.076
ClinPred
0.035
T
GERP RS
-8.9
Varity_R
0.19
gMVP
0.32

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.

Other links and lift over

dbSNP: rs779759678; hg19: chr3-37035047; API