rs1555344919

Positions:

• chr14-75046627-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001040108.2(MLH3):​c.3029A>G​(p.Glu1010Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts 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. E1010K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MLH3 NM_001040108.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.803

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18665168).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MLH3	NM_001040108.2	c.3029A>G	p.Glu1010Gly	missense_variant	2/13	ENST00000355774.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MLH3	ENST00000355774.7	c.3029A>G	p.Glu1010Gly	missense_variant	2/13	5	NM_001040108.2	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 08, 2022

The p.E1010G variant (also known as c.3029A>G), located in coding exon 1 of the MLH3 gene, results from an A to G substitution at nucleotide position 3029. The glutamic acid at codon 1010 is replaced by glycine, an amino acid with similar properties. This amino acid position is conserved. 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

Labcorp Genetics (formerly Invitae), Labcorp

Nov 09, 2019

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MLH3-related disease. This sequence change replaces glutamic acid with glycine at codon 1010 of the MLH3 protein (p.Glu1010Gly). The glutamic acid residue is weakly conserved and there is a moderate physicochemical difference between glutamic acid and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.081
BayesDel_addAF	Uncertain	0.020	T
BayesDel_noAF	Benign	-0.21
CADD	Benign	14
DANN	Uncertain	0.99
DEOGEN2	Benign	0.20	T;.;.;T
Eigen	Benign	-0.35
Eigen_PC	Benign	-0.49
FATHMM_MKL	Benign	0.18	N
LIST_S2	Benign	0.71	T;T;T;.
M_CAP	Benign	0.040	D
MetaRNN	Benign	0.19	T;T;T;T
MetaSVM	Benign	-0.91	T
MutationAssessor	Uncertain	2.5	M;M;.;M
MutationTaster	Benign	0.99	D;N;N;N;N;N
PrimateAI	Benign	0.27	T
PROVEAN	Uncertain	-2.6	D;.;D;D
REVEL	Uncertain	0.31
Sift	Uncertain	0.0030	D;.;D;D
Sift4G	Uncertain	0.0090	D;D;T;D
Polyphen		0.13	B;P;.;B
Vest4		0.12
MutPred		0.54		Gain of catalytic residue at T1013 (P = 0.0099);Gain of catalytic residue at T1013 (P = 0.0099);Gain of catalytic residue at T1013 (P = 0.0099);Gain of catalytic residue at T1013 (P = 0.0099);
MVP		0.86
MPC		0.12
ClinPred		0.85	D
GERP RS		3.8
Varity_R		0.083
gMVP		0.26

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

LitVar

Other links and lift over

dbSNP: rs1555344919; hg19: chr14-75513330;