NM_000179.3:c.113C>T

Variant names:

• chr2-47783346-C-T
• rs1553408211
• NM_000179.3:c.113C>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1 BP4_Moderate

The NM_000179.3(MSH6):​c.113C>T​(p.Pro38Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000412 in 1,457,306 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P38A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: 1.63
• Publications: 0 publications found

Genes affected

MSH6 (HGNC:7329): (mutS homolog 6) This gene encodes a member of the DNA mismatch repair MutS family. In E. coli, the MutS protein helps in the recognition of mismatched nucleotides prior to their repair. A highly conserved region of approximately 150 aa, called the Walker-A adenine nucleotide binding motif, exists in MutS homologs. The encoded protein heterodimerizes with MSH2 to form a mismatch recognition complex that functions as a bidirectional molecular switch that exchanges ADP and ATP as DNA mismatches are bound and dissociated. Mutations in this gene may be associated with hereditary nonpolyposis colon cancer, colorectal cancer, and endometrial cancer. Transcripts variants encoding different isoforms have been described. [provided by RefSeq, Jul 2013]

MSH6 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• Lynch syndrome 5

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Genomics England PanelApp
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• mismatch repair cancer syndrome 3

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P
• ovarian cancer

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

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• Muir-Torre syndrome

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

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

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

  Inheritance: AD Classification: LIMITED 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.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 25 benign, 46 uncertain in NM_000179.3
• BP4: Computational evidence support a benign effect (MetaRNN=0.1421665).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.113C>T	p.Pro38Leu	missense_variant	Exon 1 of 10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.113C>T	p.Pro38Leu	missense_variant	Exon 1 of 10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000412 AC: 6 AN: 1457306 Hom.: 0 Cov.: 30 AF XY: 0.00000414 AC XY: 3 AN XY: 724910

African (AFR) AF: 0.00 AC: 0 AN: 33228

American (AMR) AF: 0.00 AC: 0 AN: 44376

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26002

East Asian (EAS) AF: 0.0000759 AC: 3 AN: 39544

South Asian (SAS) AF: 0.00 AC: 0 AN: 85826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51992

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1110362

Other (OTH) AF: 0.00 AC: 0 AN: 60220

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Apr 07, 2020

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces proline with leucine at codon 38 of the MSH6 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in an individual affected with ovarian cancer (PMID: 23047549). This variant has not been identified 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 10, 2025

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

not specified Uncertain:1

Mar 10, 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: MSH6 c.113C>T (p.Pro38Leu) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 232580 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.113C>T has been reported in the literature a patient with ovarian cancer (Pal_2012). This report does not provide unequivocal conclusions about association of the variant with Lynch Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Dec 09, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 38 of the MSH6 protein (p.Pro38Leu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with ovarian cancer (PMID: 23047549). ClinVar contains an entry for this variant (Variation ID: 479864). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MSH6 protein function with a negative predictive value of 95%. 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. -

Endometrial carcinoma Uncertain:1

Dec 27, 2023

Baylor Genetics

Significance: Uncertain significance

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	Benign	-0.092	T
BayesDel_noAF	Benign	-0.37
CADD	Benign	18
DANN	Benign	0.81
DEOGEN2	Benign	0.28	.;T
Eigen	Benign	-0.95
Eigen_PC	Benign	-0.92
FATHMM_MKL	Benign	0.039	N
LIST_S2	Benign	0.76	T;T
M_CAP	Pathogenic	0.73	D
MetaRNN	Benign	0.14	T;T
MetaSVM	Benign	-0.68	T
MutationAssessor	Benign	0.0	N;N
PhyloP100		1.6
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-0.50	N;N
REVEL	Benign	0.23
Sift	Benign	0.30	T;T
Sift4G	Benign	0.27	T;T
Polyphen		0.0010	.;B
Vest4		0.17
MutPred		0.15		Loss of loop (P = 0.0128);Loss of loop (P = 0.0128);
MVP		0.69
ClinPred		0.12	T
GERP RS		3.5
PromoterAI		-0.0084	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.2
Varity_R		0.082
gMVP		0.28
Mutation Taster		=92/8	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: rs1553408211; hg19: chr2-48010485;