rs63751630

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_000249.4(MLH1):​c.1565G>A​(p.Arg522Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000422 in 1,613,034 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict 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: 32)
Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

5
14

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10B:4

Conservation

PhyloP100: 4.76
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 -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.18850207).
BP6
Variant 3-37040192-G-A is Benign according to our data. Variant chr3-37040192-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 89791.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Uncertain_significance=10}. Variant chr3-37040192-G-A is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
MLH1NM_000249.4 linkuse as main transcriptc.1565G>A p.Arg522Gln missense_variant 14/19 ENST00000231790.8 NP_000240.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
MLH1ENST00000231790.8 linkuse as main transcriptc.1565G>A p.Arg522Gln missense_variant 14/191 NM_000249.4 ENSP00000231790 P1P40692-1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
151930
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000657
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000319
AC:
8
AN:
251114
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135706
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
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:
0.0000431
AC:
63
AN:
1461104
Hom.:
0
Cov.:
30
AF XY:
0.0000385
AC XY:
28
AN XY:
726914
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000895
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000486
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
151930
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74174
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000657
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:10Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:1
Uncertain significance, criteria provided, single submitterclinical testingQuest Diagnostics Nichols Institute San Juan CapistranoJan 30, 2023The frequency of this variant in the general population, 0.00012 (4/34568 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in an individual with colorectal cancer, a microsatellite instability-low status, and presence of MLH1 by immunohistochemistry analysis (PMID: 16636019 (2006)), and in a subject suspected of Lynch syndrome (PMID: 25980754 (2015)). It has been reported in individuals with breast cancer as well as in unaffected controls in a large breast cancer association study (PMID: 33471991 (2021), LOVD (http://databases.lovd.nl/shared/genes/MLH1)). However, it has been predicted to be neutral from a consensus-based prediction method (PMID: 22290698 (2012)). 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. -
Likely benign, no assertion criteria providedclinical testingDepartment of Pathology and Laboratory Medicine, Sinai Health System-The MLH1 p.Arg522Gln variant was identified in 2 of 3082 proband chromosomes (frequency: 0.0006) from Dutch and American individuals or families with Lynch syndrome associated cancer or colorectal polyps (Niessen 2006, Yurgelun 2015). A novel bioinformatic prediction model PONMMR (pathogenic-or-not mismatch repair), based on the consensus from the output of 5 tolerance methods, found the variant to be neutral (Ali 2012). The variant was identified in dbSNP (ID: rs63751630) “With Uncertain significance allele”, ClinVar (classified as uncertain significance, reviewed by an expert panel (2013); submitters: uncertain significance by InSIGHT, Invitae, GeneDx, Ambry Genetics, Counsyl, Prevention Genetics and Mendelics; and likely benign by Color), and UMD-LSDB (2X classified as UV). The variant was identified in control databases in 8 of 245844 chromosomes at a frequency of 0.00003 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Latino in 4 of 33554 chromosomes (freq: 0.0001), and European Non-Finnish in 4 of 111384 chromosomes (freq: 0.00004), while not observed in the African, Other, Ashkenazi Jewish, East Asian, European Finnish, and South Asian populations. The variant was also identified by our laboratory in 1 individual, co-occurring with a pathogenic (familia) MLH1 variant (c.1609C>T,p.Q537X). The p.Arg522 residue is conserved in mammals but not in more distantly related organisms however four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood the variant Gln impacts the protein; this information is not predictive enough to rule out pathogenicity. The variant occurs outside of the splicing consensus sequence and 2 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxMay 06, 2024Observed in individuals with breast or other cancers (PMID: 25980754, 35449176, 33471991); In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 22290698, 25980754, 25085752, 22753075, 20533529, 12799449, 29641532, 32980694, 33471991, 35449176, 36243179, 16636019) -
Uncertain significance, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesDec 30, 2016- -
Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:2Benign:1
Likely benign, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Mar 15, 2023This 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 submitterclinical testingCounsylMar 16, 2017- -
Uncertain significance, criteria provided, single submitterclinical testingBaylor GeneticsFeb 26, 2024- -
Hereditary cancer-predisposing syndrome Uncertain:1Benign:2
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsSep 21, 2020This 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. -
Likely benign, criteria provided, single submitterclinical testingColor Diagnostics, LLC DBA Color HealthApr 21, 2015- -
Uncertain significance, criteria provided, single submittercurationSema4, Sema4Oct 15, 2021- -
not specified Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingCenter for Genomic Medicine, Rigshospitalet, Copenhagen University HospitalAug 15, 2023- -
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpMay 13, 2024Variant summary: MLH1 c.1565G>A (p.Arg522Gln) results in a conservative amino acid change located in the DNA mismatch repair protein Mlh1, C-terminal domain (IPR032189) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. A bioinformatic MMR consensus classifier called PON-MMR predicts this variant as having a neutral outcome (Ali_2012). The variant allele was found at a frequency of 3.2e-05 in 251114 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1565G>A has been reported in the literature as a VUS in settings of multigene panel testing in individuals affected with colorectal cancer (example, Niessen_2006, Yurgelun_2015). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Nonpolyposis Colorectal Cancer. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. ClinVar contains an entry for this variant (Variation ID: 89791). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingMendelicsJul 02, 2018- -
Hereditary nonpolyposis colorectal neoplasms Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 522 of the MLH1 protein (p.Arg522Gln). This variant is present in population databases (rs63751630, gnomAD 0.01%). This missense change has been observed in individual(s) with clinical features of MLH1-related conditions or breast cancer (PMID: 10612827, 25980754, 35449176). ClinVar contains an entry for this variant (Variation ID: 89791). 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%. RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (Invitae). 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
Benign
0.068
BayesDel_addAF
Benign
-0.037
T
BayesDel_noAF
Uncertain
-0.070
CADD
Benign
19
DANN
Benign
0.85
DEOGEN2
Uncertain
0.54
D;.;.;.;.;.;D
Eigen
Benign
-0.39
Eigen_PC
Benign
-0.22
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Uncertain
0.87
D;D;.;.;.;D;D
M_CAP
Benign
0.061
D
MetaRNN
Benign
0.19
T;T;T;T;T;T;T
MetaSVM
Benign
-0.55
T
MutationAssessor
Benign
0.48
N;.;.;.;.;.;.
MutationTaster
Benign
1.0
D;D;D;D;D;D
PrimateAI
Benign
0.28
T
PROVEAN
Benign
-0.38
N;N;N;N;N;N;N
REVEL
Uncertain
0.46
Sift
Benign
0.28
T;T;T;T;T;T;T
Sift4G
Benign
0.46
T;T;T;T;T;T;T
Polyphen
0.0
B;.;.;.;.;.;.
Vest4
0.45
MutPred
0.42
Gain of sheet (P = 0.0344);.;.;.;.;.;.;
MVP
0.95
MPC
0.075
ClinPred
0.083
T
GERP RS
4.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.21
gMVP
0.32

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs63751630; hg19: chr3-37081683; API