rs267608076

Positions:

• chr2-47799617-AAG-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000179.3(MSH6):​c.1637_1638del​(p.Glu546GlyfsTer16) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000137 in 1,461,876 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MSH6 NM_000179.3 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:11
• Conservation: PhyloP100: 3.80

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]

FBXO11 (HGNC:13590): (F-box protein 11) This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. It can function as an arginine methyltransferase that symmetrically dimethylates arginine residues, and it acts as an adaptor protein to mediate the neddylation of p53, which leads to the suppression of p53 function. This gene is known to be down-regulated in melanocytes from patients with vitiligo, a skin disorder that results in depigmentation. Polymorphisms in this gene are associated with chronic otitis media with effusion and recurrent otitis media (COME/ROM), a hearing loss disorder, and the knockout of the homologous mouse gene results in the deaf mouse mutant Jeff (Jf), a single gene model of otitis media. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-47799617-AAG-A is Pathogenic according to our data. Variant chr2-47799617-AAG-A is described in ClinVar as [Pathogenic]. Clinvar id is 89213.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr2-47799617-AAG-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH6	NM_000179.3	c.1637_1638del	p.Glu546GlyfsTer16	frameshift_variant	4/10	ENST00000234420.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH6	ENST00000234420.11	c.1637_1638del	p.Glu546GlyfsTer16	frameshift_variant	4/10	1	NM_000179.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461876 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 727234

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:11

Revision: reviewed by expert panel

Submissions by phenotype

Lynch syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Oct 31, 2023	This variant deletes 2 nucleotides in exon 4 of the MSH6 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. Computational splicing tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in families affected with Lynch syndrome-associated cancers (PMID: 16885385, 20028993, 25559809). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of MSH6 function is a known mechanism of disease. Based on available evidence, this variant is classified as Pathogenic. -
Pathogenic, reviewed by expert panel	research	International Society for Gastrointestinal Hereditary Tumours (InSiGHT)	Sep 05, 2013	Coding sequence variation resulting in a stop codon -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Nov 11, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jan 15, 2023	Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as c.1635_1636delAG; This variant is associated with the following publications: (PMID: 16885385, 20028993, 25559809, 30787465, 29489754, 26787237, 30256826) -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 04, 2023	This variant deletes 2 nucleotides in exon 4 of the MSH6 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has been reported in individuals affected with Lynch syndrome and Lynch syndrome-associated disease (PMID: 16885385, 20028993, 25559809, 26787237, 27329137, 30256826). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of MSH6 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 12, 2021	The c.1637_1638delAG pathogenic mutation, located in coding exon 4 of the MSH6 gene, results from a deletion of two nucleotides at nucleotide positions 1637 to 1638, causing a translational frameshift with a predicted alternate stop codon (p.E546Gfs*16). This pathogenic mutation has been reported in individuals with personal and family histories of Lynch syndrome related cancers (Hampel H et al. Cancer Res. 2006 Aug; 66(15):7810-7; Chubb D et al. J. Clin. Oncol. 2015 Feb; 33(5):426-32; Meric-Bernstam F et al. Ann. Oncol. 2016 May; 27(5):795-800; Martin-Morales L et al. PLoS One, 2018 Sep;13:e0203885). Of note, this alteration is also designated as c.1635_1636delAG in published literature. This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Lynch syndrome 5 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Aug 15, 2023

This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -

Hereditary nonpolyposis colon cancer Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Jun 07, 2023

Variant summary: MSH6 c.1637_1638delAG (p.Glu546GlyfsX16) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant was absent in 251216 control chromosomes (gnomAD, v2.1). c.1637_1638delAG has been reported in the literature in individuals affected with Lynch syndrome (e.g., Baglietto_2010, Chubb_2015, Hampel_2006). These data indicate that the variant is likely to be associated with disease. The following publications have been ascertained in the context of this evaluation (PMID: 16885385, 20028993, 25559809). Six ClinVar submitters (evaluation after 2014) have cited the variant, and all submitters classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Gastric cancer Pathogenic:1

Pathogenic, no assertion criteria provided

research

Laboratory for Genotyping Development, RIKEN

Jul 01, 2021

- -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 16, 2023

This sequence change creates a premature translational stop signal (p.Glu546Glyfs*16) in the MSH6 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MSH6 are known to be pathogenic (PMID: 18269114, 24362816). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with Lynch syndrome-associated cancers (PMID: 16885385, 20028993, 25559809, 26787237). This variant is also known as c.1635_1636delAG. ClinVar contains an entry for this variant (Variation ID: 89213). For these reasons, this variant has been classified as Pathogenic. -

Endometrial carcinoma Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Nov 29, 2021

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs267608076; hg19: chr2-48026756;