rs376224686

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PP3BS1_Supporting

The NM_001040108.2(MLH3):​c.4135C>T​(p.Arg1379Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000113 in 1,613,986 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1379H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 30)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

MLH3
NM_001040108.2 missense

Scores

2
11
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.29

Publications

1 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: Uncertain_significance. The variant received 0 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.789
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.000123 (180/1461876) while in subpopulation NFE AF = 0.000156 (174/1111994). AF 95% confidence interval is 0.000137. There are 0 homozygotes in GnomAdExome4. There are 81 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001040108.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MLH3
NM_001040108.2
MANE Select
c.4135C>Tp.Arg1379Cys
missense
Exon 12 of 13NP_001035197.1
MLH3
NM_014381.3
c.4063C>Tp.Arg1355Cys
missense
Exon 11 of 12NP_055196.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MLH3
ENST00000355774.7
TSL:5 MANE Select
c.4135C>Tp.Arg1379Cys
missense
Exon 12 of 13ENSP00000348020.2
MLH3
ENST00000380968.6
TSL:1
c.4063C>Tp.Arg1355Cys
missense
Exon 11 of 12ENSP00000370355.3
MLH3
ENST00000556257.5
TSL:5
c.3601C>Tp.Arg1201Cys
missense
Exon 6 of 7ENSP00000451540.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152110
Hom.:
0
Cov.:
30
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000358
AC:
9
AN:
251474
AF XY:
0.0000368
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:
0.0000615
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000123
AC:
180
AN:
1461876
Hom.:
0
Cov.:
32
AF XY:
0.000111
AC XY:
81
AN XY:
727242
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:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000156
AC:
174
AN:
1111994
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
8
17
25
34
42
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000197
AC:
3
AN:
152110
Hom.:
0
Cov.:
30
AF XY:
0.0000135
AC XY:
1
AN XY:
74306
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41408
American (AMR)
AF:
0.0000655
AC:
1
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
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:
0.0000612
Hom.:
0
Bravo
AF:
0.0000340
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000178

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Nov 08, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R1379C variant (also known as c.4135C>T), located in coding exon 11 of the MLH3 gene, results from a C to T substitution at nucleotide position 4135. The arginine at codon 1379 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Colorectal cancer, hereditary nonpolyposis, type 7 Uncertain:1
Nov 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1379 of the MLH3 protein (p.Arg1379Cys). This variant is present in population databases (rs376224686, gnomAD 0.006%). 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: 570136). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.013
T
BayesDel_noAF
Uncertain
-0.080
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.39
T
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.93
D
M_CAP
Benign
0.069
D
MetaRNN
Pathogenic
0.79
D
MetaSVM
Uncertain
0.53
D
MutationAssessor
Uncertain
2.8
M
PhyloP100
4.3
PrimateAI
Benign
0.33
T
PROVEAN
Uncertain
-4.1
D
REVEL
Uncertain
0.42
Sift
Uncertain
0.0020
D
Sift4G
Uncertain
0.0040
D
Polyphen
1.0
D
Vest4
0.51
MVP
0.91
MPC
0.54
ClinPred
0.93
D
GERP RS
5.7
Varity_R
0.61
gMVP
0.36
Mutation Taster
=71/29
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs376224686; hg19: chr14-75485639; API