rs754716792

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PVS1

The NM_001040108.2(MLH3):​c.2793_2794delGA​(p.Asn932TrpfsTer13) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000743 in 1,613,990 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

MLH3
NM_001040108.2 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 0.113

Publications

0 publications found
Variant links:
Genes affected
MLH3 (HGNC:7128): (mutL homolog 3) This gene is a member of the MutL-homolog (MLH) family of DNA mismatch repair (MMR) genes. MLH genes are implicated in maintaining genomic integrity during DNA replication and after meiotic recombination. The protein encoded by this gene functions as a heterodimer with other family members. Somatic mutations in this gene frequently occur in tumors exhibiting microsatellite instability, and germline mutations have been linked to hereditary nonpolyposis colorectal cancer type 7 (HNPCC7). Several alternatively spliced transcript variants have been identified, but the full-length nature of only two transcript variants has been determined. [provided by RefSeq, Jul 2008]
MLH3 Gene-Disease associations (from GenCC):
  • colorectal cancer, hereditary nonpolyposis, type 7
    Inheritance: AD, AR Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, ClinGen, Laboratory for Molecular Medicine

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MLH3NM_001040108.2 linkc.2793_2794delGA p.Asn932TrpfsTer13 frameshift_variant Exon 2 of 13 ENST00000355774.7 NP_001035197.1 Q9UHC1-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MLH3ENST00000355774.7 linkc.2793_2794delGA p.Asn932TrpfsTer13 frameshift_variant Exon 2 of 13 5 NM_001040108.2 ENSP00000348020.2 Q9UHC1-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152240
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:
0.0000119
AC:
3
AN:
251298
AF XY:
0.00000736
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:
0.00000753
AC:
11
AN:
1461750
Hom.:
0
AF XY:
0.00000550
AC XY:
4
AN XY:
727170
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53310
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000899
AC:
10
AN:
1112000
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.00000657
AC:
1
AN:
152240
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74378
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 7 Uncertain:2
Apr 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Asn932Trpfs*13) in the MLH3 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in MLH3 cause disease. This variant is present in population databases (rs754716792, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with MLH3-related conditions. ClinVar contains an entry for this variant (Variation ID: 419010). 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. -

Nov 21, 2018
Equipe Genetique des Anomalies du Developpement, Université de Bourgogne
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jul 11, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2793_2794delGA variant, located in coding exon 1 of the MLH3 gene, results from a deletion of two nucleotides at nucleotide positions 2793 to 2794, causing a translational frameshift with a predicted alternate stop codon (p.N932Wfs*13). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. The evidence for this gene-disease relationship is limited; therefore, the clinical significance of this alteration is unclear. -

not provided Uncertain:1
Oct 02, 2018
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2793_2794delGA variant in the MLH3 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The c.2793_2794delGA variant causes a frameshift starting with codon Asparagine 932, changes this amino acid to a Tryptophan residue and creates a premature Stop codon at position 13 of the new reading frame, denoted p.Asn932TrpfsX13. This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The c.2793_2794delGA variant is observed in 2/111,646 (0.002%) alleles from individuals of non-Finnish European background in large population cohorts (Lek et al., 2016). We interpret c.2793_2794delGA as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.11
Mutation Taster
=19/181
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs754716792; hg19: chr14-75513564; API