NM_001040108.2:c.41G>A

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_001040108.2(MLH3):c.41G>A(p.Arg14His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,614,026 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. R14C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

MLH3
NM_001040108.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.90

Publications

3 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

MLH3 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.907

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	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH3	NM_001040108.2	MANE Select	c.41G>A	p.Arg14His	missense	Exon 2 of 13	NP_001035197.1
	MLH3	NM_014381.3		c.41G>A	p.Arg14His	missense	Exon 2 of 12	NP_055196.2

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
MLH3	ENST00000355774.7	TSL:5 MANE Select	c.41G>A	p.Arg14His	missense	Exon 2 of 13	ENSP00000348020.2
MLH3	ENST00000380968.6	TSL:1	c.41G>A	p.Arg14His	missense	Exon 2 of 12	ENSP00000370355.3
MLH3	ENST00000556257.5	TSL:5	c.41G>A	p.Arg14His	missense	Exon 2 of 7	ENSP00000451540.1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152148

Hom.:

Cov.:

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:

0.00000398

AC:

AN:

251344

AF XY:

0.00

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:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000178

AC:

AN:

1461878

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

727234

show subpopulations

African (AFR)

AF:

0.0000597

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000232

AC:

AN:

86256

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53416

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000189

AC:

AN:

1112002

Other (OTH)

AF:

0.0000166

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.515

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

AN:

152148

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74308

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41430

American (AMR)

AF:

0.00

AC:

AN:

15274

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5200

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10596

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68032

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.000144

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:2

Jul 03, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.R14H variant (also known as c.41G>A), located in coding exon 1 of the MLH3 gene, results from a G to A substitution at nucleotide position 41. The arginine at codon 14 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. The evidence for this gene-disease relationship is limited; therefore, the clinical significance of this alteration is unclear.

Mar 04, 2025

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Colorectal cancer, hereditary nonpolyposis, type 7

Uncertain:1

Jul 30, 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 histidine, which is basic and polar, at codon 14 of the MLH3 protein (p.Arg14His). This variant is present in population databases (rs760072474, gnomAD 0.003%). 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: 544268). 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

0.29

BayesDel_addAF

Pathogenic

0.42

BayesDel_noAF

Pathogenic

0.46

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.45

Eigen

Pathogenic

0.90

Eigen_PC

Pathogenic

0.85

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.96

M_CAP

Uncertain

0.18

MetaRNN

Pathogenic

0.91

MetaSVM

Pathogenic

0.91

MutationAssessor

Uncertain

2.9

PhyloP100

7.9

PrimateAI

Uncertain

0.56

PROVEAN

Uncertain

-4.4

REVEL

Pathogenic

0.91

Sift

Uncertain

0.0010

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.79

MVP

0.98

MPC

0.57

ClinPred

1.0

GERP RS

5.5

Varity_R

0.57

gMVP

0.60

Mutation Taster

=167/133

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over