rs772538373

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 2P and 8B. PM5BP4_StrongBS2

The NM_001040108.2(MLH3):c.2174A>G(p.Asn725Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,992 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 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. N725K) has been classified as Uncertain significance.

Frequency

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

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

MLH3
NM_001040108.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: -0.396

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.

PM5

Other missense variant is known to change same aminoacid residue: Variant chr14-75047483-T-G is described in Lovd as [Likely_pathogenic].

BP4

Computational evidence support a benign effect (MetaRNN=0.045791).

BS2

High AC in GnomAdExome at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MLH3	NM_001040108.2 linkuse as main transcript	c.2174A>G	p.Asn725Ser	missense_variant	2/13	ENST00000355774.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MLH3	ENST00000355774.7 linkuse as main transcript	c.2174A>G	p.Asn725Ser	missense_variant	2/13	5	NM_001040108.2	P1	Q9UHC1-1
MLH3	ENST00000380968.6 linkuse as main transcript	c.2174A>G	p.Asn725Ser	missense_variant	2/12	1			Q9UHC1-2
MLH3	ENST00000556257.5 linkuse as main transcript	c.2174A>G	p.Asn725Ser	missense_variant	2/7	5

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000318

AC:

AN:

251338

Hom.:

AF XY:

0.0000294

AC XY:

AN XY:

135854

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.000116

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000684

AC:

AN:

1461802

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727194

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000360

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.0000565

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.0000330

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

Feb 08, 2023

The p.N725S variant (also known as c.2174A>G), located in coding exon 1 of the MLH3 gene, results from an A to G substitution at nucleotide position 2174. The asparagine at codon 725 is replaced by serine, an amino acid with highly 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

Apr 15, 2023

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: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The serine 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: 478024). This variant has not been reported in the literature in individuals affected with MLH3-related conditions. This variant is present in population databases (rs772538373, gnomAD 0.01%). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 725 of the MLH3 protein (p.Asn725Ser). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.064

BayesDel_addAF

Benign

-0.54

BayesDel_noAF

Benign

-0.78

Cadd

Benign

0.051

Dann

Benign

0.50

DEOGEN2

Benign

0.10

T;.;.;T

Eigen

Benign

-1.7

Eigen_PC

Benign

-1.8

FATHMM_MKL

Benign

0.027

LIST_S2

Benign

0.59

T;T;T;.

M_CAP

Benign

0.0074

MetaRNN

Benign

0.046

T;T;T;T

MetaSVM

Benign

-0.98

MutationAssessor

Benign

1.7

L;L;.;L

MutationTaster

Benign

1.0

N;N;N;N;N

PrimateAI

Benign

0.22

PROVEAN

Benign

-1.3

N;.;N;N

REVEL

Benign

0.042

Sift

Benign

0.34

T;.;T;T

Sift4G

Benign

0.47

T;T;T;T

Polyphen

0.013

B;B;.;B

Vest4

0.058

MVP

0.26

MPC

0.080

ClinPred

0.062

GERP RS

-9.0

Varity_R

0.031

gMVP

0.13

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

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