chr3-37040191-C-T

Variant summary

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

The NM_000249.4(MLH1):​c.1564C>T​(p.Arg522Trp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000192 in 1,612,972 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. R522Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

MLH1
NM_000249.4 missense

Scores

4
12
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:2

Conservation

PhyloP100: 7.70
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 -1 ACMG points.

BP6
Variant 3-37040191-C-T is Benign according to our data. Variant chr3-37040191-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 216331.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=9}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MLH1NM_000249.4 linkc.1564C>T p.Arg522Trp missense_variant Exon 14 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.1564C>T p.Arg522Trp missense_variant Exon 14 of 19 1 NM_000249.4 ENSP00000231790.3 P40692-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
151966
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000159
AC:
4
AN:
251108
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135698
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:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000192
AC:
28
AN:
1461006
Hom.:
0
Cov.:
30
AF XY:
0.0000261
AC XY:
19
AN XY:
726884
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.0000187
Gnomad4 NFE exome
AF:
0.0000189
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
151966
Hom.:
0
Cov.:
32
AF XY:
0.0000270
AC XY:
2
AN XY:
74200
show subpopulations
Gnomad4 AFR
AF:
0.0000242
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:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000659
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:4
Dec 12, 2017
PreventionGenetics, part of Exact Sciences
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 06, 2016
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: The MLH1 c.1564C>T (p.Arg522Trp) variant involves the alteration of a conserved nucleotide. 3/4 in silico tools predict a damaging outcome (SNPs&GO not captured due to low reliability index). This variant was found in 4/121218 control chromosomes at a frequency of 0.000033, which does not exceed the estimated maximal expected allele frequency of a pathogenic MLH1 variant (0.0007105). In addition, multiple clinical diagnostic laboratories classified this variant as VUS, without evidence to independently evaluate. This variant, to our knowledge, has not been reported as a germ-line variant in affected individuals. One study showed this variant with protein expression level not significantly different from WT (Hinrichsen_2013). Because of the absence of clinical information and the lack of functional studies, the variant was classified as a variant of uncertain significance (VUS) until additional information becomes available. -

May 27, 2022
Clinical Genetics Laboratory, Skane University Hospital Lund
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 13, 2023
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 has a deleterious effect on protein structure/function; Observed in an individual with personal/family history suspicious for Lynch syndrome (Lagerstedt-Robinson et al., 2016); Published functional studies are inconclusive: slightly reduced protein expression but mismatch repair activity comparable to wild-type (Hinrichsen et al., 2013); This variant is associated with the following publications: (PMID: 26976419, 14688830, 24362816, 22753075, 12799449, 20533529, 23403630, 27601186) -

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

- -

Apr 15, 2016
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Aug 20, 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]. -

Hereditary cancer-predisposing syndrome Uncertain:2
Jan 17, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R522W variant (also known as c.1564C>T), located in coding exon 14 of the MLH1 gene, results from a C to T substitution at nucleotide position 1564. The arginine at codon 522 is replaced by tryptophan, an amino acid with dissimilar properties. This variant was reported in a Swedish family suspected to have Lynch syndrome, but no clinical or family history information was provided (Lagerstedt-Robinson K et al. Oncol. Rep. 2016 Nov;36(5):2823-2835). In another study, the p.R522W alteration was detected as a somatic alteration in a Dukes' B2 colon cancer that exhibited microsatellite stability (Kámory E et al. Pathol. Oncol. Res. 2003;9(4): 236-41). Functional analyses of this alteration using quantitative PCR, pulse-chase and thermal stability indicate that p.R522W does not have a significant decrease in expression or MMR proficiency compared to wild-type (Hinrichsen I et al. Clin. Cancer Res. 2013 May;19(9):2432-41). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Sep 14, 2023
Color Diagnostics, LLC DBA Color Health
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces arginine with tryptophan at codon 522 of the MLH1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). An experimental functional study has shown this variant had normal mismatch repair activity and only a moderate impact on MLH1 expression (PMID: 23403630). This variant has been reported in an individual suspected of having Lynch syndrome (PMID: 27601186). This variant has been identified in 5/282468 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. -

Lynch syndrome Uncertain:1
Jun 17, 2024
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 arginine with tryptophan at codon 522 of the MLH1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. An experimental functional study has shown this variant had normal mismatch repair activity and only a moderate impact on MLH1 expression (PMID: 23403630). This variant has been reported in an individual suspected of having Lynch syndrome in the literature (PMID: 27601186). This variant has been identified in 5/282468 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
Jan 05, 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
0.12
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Pathogenic
0.14
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.89
D;.;.;.;.;.;D
Eigen
Uncertain
0.20
Eigen_PC
Uncertain
0.29
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;D;.;.;.;D;D
M_CAP
Uncertain
0.21
D
MetaRNN
Uncertain
0.62
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.24
D
MutationAssessor
Uncertain
2.4
M;.;.;.;.;.;.
PrimateAI
Benign
0.35
T
PROVEAN
Uncertain
-4.2
D;D;D;D;D;D;D
REVEL
Uncertain
0.48
Sift
Uncertain
0.0030
D;D;D;D;D;D;D
Sift4G
Uncertain
0.0070
D;D;D;D;D;D;T
Polyphen
0.12
B;.;.;.;.;.;.
Vest4
0.60
MutPred
0.48
Loss of disorder (P = 0.0108);.;.;.;.;.;.;
MVP
0.84
MPC
0.12
ClinPred
0.87
D
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.70
gMVP
0.63

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
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: rs63751703; hg19: chr3-37081682; COSMIC: COSV51618540; API