rs749204990

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP6_Very_StrongBP7

The NM_000249.4(MLH1):​c.1665T>C​(p.Leu555Leu) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,608,946 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000026 ( 0 hom. )

Consequence

MLH1
NM_000249.4 splice_region, synonymous

Scores

2
Splicing: ADA: 0.00001338
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: -0.0430

Publications

5 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: Benign. The variant received -9 ACMG points.

BP6
Variant 3-37040292-T-C is Benign according to our data. Variant chr3-37040292-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 187733.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.043 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MLH1NM_000249.4 linkc.1665T>C p.Leu555Leu splice_region_variant, synonymous_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.1665T>C p.Leu555Leu splice_region_variant, synonymous_variant Exon 14 of 19 1 NM_000249.4 ENSP00000231790.3 P40692-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152036
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251244
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000261
AC:
38
AN:
1456910
Hom.:
0
Cov.:
29
AF XY:
0.0000234
AC XY:
17
AN XY:
725184
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33372
American (AMR)
AF:
0.0000224
AC:
1
AN:
44706
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39656
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86180
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53386
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000316
AC:
35
AN:
1107504
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60246
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
3
6
8
11
14
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:
0.00000658
AC:
1
AN:
152036
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74252
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41398
American (AMR)
AF:
0.00
AC:
0
AN:
15250
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10582
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:2
Aug 30, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: MLH1 c.1665T>C (p.Leu555Leu) alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 5/5 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 8e-06 in 251244 control chromosomes. 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.1665T>C in individuals affected with Lynch Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Three laboratories have submitted clinical-significance assessments for this variant to ClinVar (evaluation after 2014) and cited the variant as likely benign. Based on the evidence outlined above, the variant was classified as likely benign. -

Oct 24, 2017
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Hereditary cancer-predisposing syndrome Benign:2
Dec 29, 2014
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. -

Jun 05, 2017
Color Diagnostics, LLC DBA Color Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Colorectal cancer, hereditary nonpolyposis, type 2 Benign:1
Nov 25, 2024
Myriad Genetics, Inc.
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered benign. This variant is a silent/synonymous amino acid change and it is not expected to impact splicing. -

Lynch syndrome Benign:1
Aug 28, 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
Dec 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.59
CADD
Benign
0.19
DANN
Benign
0.43
PhyloP100
-0.043

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000013
dbscSNV1_RF
Benign
0.014
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

Other links and lift over

dbSNP: rs749204990; hg19: chr3-37081783; API