rs587779956

Variant names:

• chr3-37047621-G-A
• rs587779956
• NM_000249.4:c.1834G>A

Your query was ambiguous. Multiple possible variants found:

• chr3-37047621-G-A
• chr3-37047621-G-C
• chr3-37047621-G-T

Variant summary

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

The NM_000249.4(MLH1):​c.1834G>A​(p.Val612Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,174 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 31)
• Consequence: MLH1 NM_000249.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:8 B:2
• Conservation: PhyloP100: 7.88

Genes affected

MLH1 (HGNC:7127): (mutL homolog 1) The protein encoded by this gene can heterodimerize with mismatch repair endonuclease PMS2 to form MutL alpha, part of the DNA mismatch repair system. When MutL alpha is bound by MutS beta and some accessory proteins, the PMS2 subunit of MutL alpha introduces a single-strand break near DNA mismatches, providing an entry point for exonuclease degradation. The encoded protein is also involved in DNA damage signaling and can heterodimerize with DNA mismatch repair protein MLH3 to form MutL gamma, which is involved in meiosis. This gene was identified as a locus frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH1	NM_000249.4	c.1834G>A	p.Val612Ile	missense_variant	Exon 16 of 19	ENST00000231790.8	NP_000240.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MLH1	ENST00000231790.8	c.1834G>A	p.Val612Ile	missense_variant	Exon 16 of 19	1	NM_000249.4	ENSP00000231790.3

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152174 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.00000398 AC: 1 AN: 251412 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135876

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

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 Cov.: 31

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152174 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 74336

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000131

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

Bravo AF: 0.0000227

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:8 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:3

Feb 17, 2022

Sema4, Sema4

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

- -

Oct 11, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces valine with isoleucine at codon 612 of the MLH1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 32658311). This variant has been identified in 2/282810 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Jan 03, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V612I variant (also known as c.1834G>A), located in coding exon 16 of the MLH1 gene, results from a G to A substitution at nucleotide position 1834. The valine at codon 612 is replaced by isoleucine, an amino acid with highly similar properties. This alteration was seen in 1/732 breast cancer patients, 0/189 colorectal cancer patients and 0/490 cancer-free elderly controls in a Turkish population (Akcay IM et al. Int J Cancer, 2021 01;148:285-295). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

not provided Uncertain:2

Nov 15, 2022

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 12799449, 20533529, 22753075) -

Mar 06, 2020

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:1 Benign:1

Nov 26, 2024

Myriad Genetics, Inc.

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign. Homozygosity for this variant has been confirmed in one or more individuals lacking clinical features consistent with gene-specific recessive disease, indicating that this variant is unlikely to be pathogenic. -

Oct 24, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified Uncertain:1

Sep 14, 2020

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: MLH1 c.1834G>A (p.Val612Ile) results in a conservative amino acid change located in the DNA mismatch repair protein Mlh1, C-terminal domain (IPR032189) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251412 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1834G>A in individuals affected with Hereditary Nonpolyposis Colorectal Cancer and no experimental evidence demonstrating its impact on protein function have been reported. Four ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Lynch syndrome Uncertain:1

Nov 02, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces valine with isoleucine at codon 612 of the MLH1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 32658311). This variant has been identified in 2/282810 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Dec 10, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Pathogenic	0.14
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.66	D;.;.;.;.;.
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	D;D;.;.;.;D
M_CAP	Uncertain	0.12	D
MetaRNN	Uncertain	0.44	T;T;T;T;T;T
MetaSVM	Uncertain	0.73	D
MutationAssessor	Uncertain	2.5	M;.;.;.;.;.
PrimateAI	Uncertain	0.65	T
PROVEAN	Benign	-0.92	N;N;N;N;N;N
REVEL	Uncertain	0.59
Sift	Benign	0.075	T;D;D;D;D;T
Sift4G	Benign	0.13	T;T;T;T;T;T
Polyphen		0.81	P;.;.;.;.;.
Vest4		0.58
MutPred		0.34		Gain of methylation at K617 (P = 0.1098);.;.;.;.;.;
MVP		0.83
MPC		0.094
ClinPred		0.65	D
GERP RS		5.3
Varity_R		0.38
gMVP		0.52

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

Other links and lift over

dbSNP: rs587779956; hg19: chr3-37089112;