3-37012059-G-T

Variant names:

• chr3-37012059-G-T
• rs2308317
• ENST00000458205.6:c.-87G>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The ENST00000458205.6(MLH1):​c.-87G>T variant causes a 5 prime UTR premature start codon gain change. The variant allele was found at a frequency of 0.000000684 in 1,461,660 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MLH1 ENST00000458205.6 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 5.28
• Publications: 25 publications found

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]

MLH1 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• Lynch syndrome 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp
• Muir-Torre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Orphanet
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
• Lynch syndrome 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• ovarian cancer

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• prostate cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• breast cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.21210325).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH1	NM_000249.4	c.637G>T	p.Val213Leu	missense_variant	Exon 8 of 19	ENST00000231790.8	NP_000240.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MLH1	ENST00000231790.8	c.637G>T	p.Val213Leu	missense_variant	Exon 8 of 19	1	NM_000249.4	ENSP00000231790.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251170 AF XY: 0.0000147

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461660 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727154

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111812

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Nov 16, 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 leucine at codon 213 of the MLH1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). A functional study demonstrated this variant has no impact on RNA or protein expression (PMID: 28494185). This variant has been reported in a family affected with Lynch syndrome (PMID: 16810763, 15613555). This variant has been identified in 2/251170 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. -

Feb 15, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V213L variant (also known as c.637G>T), located in coding exon 8 of the MLH1 gene, results from a G to T substitution at nucleotide position 637. The valine at codon 213 is replaced by leucine, an amino acid with highly similar properties. This alteration has been reported in a Chinese HNPCC family; however, no additional clinical details of the family were outlined (Wang XL et al. World J. Gastroenterol. 2006 Jul;12(25):4074-7). Functional studies have shown that this alteration results in both protein expression and mRNA expression similar to that of wild-type MLH1 (Arora S et al. Cancer Biol. Ther. 2017 Jul;18(7):519-533). This alteration was also identified in 1 of 1009 patients amongst a cohort of Chinese patients with a personal history of pancreatic ductal adenocarcinoma (Yin L et al. JAMA Netw Open, 2022 Feb;5:e2148721). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:1

Oct 03, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Lynch syndrome Uncertain:1

Dec 13, 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 leucine at codon 213 of the MLH1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). A functional study demonstrated this variant has no impact on RNA or protein expression (PMID: 28494185). This variant has been reported in a family affected with Lynch syndrome (PMID: 16810763, 15613555). This variant has been identified in 2/251170 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 Uncertain:1

Nov 18, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 213 of the MLH1 protein (p.Val213Leu). This variant is present in population databases (rs2308317, gnomAD 0.01%). This missense change has been observed in individual(s) with clinical features of MLH1-related conditions (PMID: 16810763, 17074586, 35171259). ClinVar contains an entry for this variant (Variation ID: 90300). Invitae Evidence Modeling incorporating data from in vitro experimental studies (internal data) indicates that this missense variant is not expected to disrupt MLH1 function with a negative predictive value of 95%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on MLH1 function (PMID: 28494185). 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 v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	0.00054	T
BayesDel_noAF	Uncertain	-0.010
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Benign	0.35	T;.
Eigen	Benign	-0.11
Eigen_PC	Benign	0.15
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.93	D;D
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.21	T;T
MetaSVM	Benign	-0.72	T
MutationAssessor	Benign	0.23	N;.
PhyloP100		5.3
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-0.69	N;N
REVEL	Uncertain	0.33
Sift	Benign	0.32	T;T
Sift4G	Benign	0.45	T;T
Polyphen		0.0010	B;.
Vest4		0.36
MutPred		0.27		Gain of helix (P = 0.2684);.;
MVP		0.88
MPC		0.068
ClinPred		0.22	T
GERP RS		5.8
Varity_R		0.21
gMVP		0.56
Mutation Taster		=55/45	polymorphism

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

Other links and lift over

dbSNP: rs2308317; hg19: chr3-37053550;