rs140127407

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_001040108.2(MLH3):c.3356C>T(p.Thr1119Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,613,980 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign 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. T1119A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

MLH3
NM_001040108.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 0.692

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.082917094).

BS2

High AC in GnomAd at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MLH3	NM_001040108.2 linkuse as main transcript	c.3356C>T	p.Thr1119Ile	missense_variant	3/13	ENST00000355774.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MLH3	ENST00000355774.7 linkuse as main transcript	c.3356C>T	p.Thr1119Ile	missense_variant	3/13	5	NM_001040108.2	P1	Q9UHC1-1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152154

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000145

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251486

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135920

show subpopulations

Gnomad AFR exome

AF:

0.000185

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461826

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727230

show subpopulations

Gnomad4 AFR exome

AF:

0.0000896

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152154

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74314

show subpopulations

Gnomad4 AFR

AF:

0.000145

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:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.0000453

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 14, 2023

The p.T1119I variant (also known as c.3356C>T), located in coding exon 2 of the MLH3 gene, results from a C to T substitution at nucleotide position 3356. The threonine at codon 1119 is replaced by isoleucine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Colorectal cancer, hereditary nonpolyposis, type 7

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 20, 2022

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 1119 of the MLH3 protein (p.Thr1119Ile). 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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The isoleucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 410895). This variant has not been reported in the literature in individuals affected with MLH3-related conditions. This variant is present in population databases (rs140127407, gnomAD 0.01%). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.23

Cadd

Benign

Dann

Uncertain

0.99

DEOGEN2

Benign

0.088

T;.;T

Eigen

Benign

-0.59

Eigen_PC

Benign

-0.57

FATHMM_MKL

Benign

0.35

LIST_S2

Benign

0.58

T;T;.

M_CAP

Benign

0.044

MetaRNN

Benign

0.083

T;T;T

MetaSVM

Benign

-0.69

MutationAssessor

Benign

1.7

L;L;L

MutationTaster

Benign

1.0

N;N;N;N;N;N

PrimateAI

Benign

0.40

PROVEAN

Benign

-0.60

N;.;N

REVEL

Benign

0.069

Sift

Benign

0.083

T;.;T

Sift4G

Uncertain

0.020

D;D;D

Polyphen

0.013

B;B;B

Vest4

0.14

MVP

0.79

MPC

0.11

ClinPred

0.044

GERP RS

3.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.034

gMVP

0.24

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.050

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over