rs786203924

Positions:

• chr2-47800887-CTA-C

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.2906_2907delAT​(p.Tyr969fs) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,453,856 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 criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 7.99

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]

MSH6 (HGNC:):

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 2-47800887-CTA-C is Pathogenic according to our data. Variant chr2-47800887-CTA-C is described in ClinVar as [Pathogenic]. Clinvar id is 187691.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-47800887-CTA-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH6	NM_000179.3	c.2906_2907delAT	p.Tyr969fs	frameshift_variant	4/10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.2906_2907delAT	p.Tyr969fs	frameshift_variant	4/10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1453856 Hom.: 0 AF XY: 0.00000138 AC XY: 1 AN XY: 722470

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

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	May 07, 2023	This frameshift variant alters the translational reading frame of the MSH6 mRNA and causes the premature termination of MSH6 protein synthesis. This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). In the published literature, the variant has been reported in individuals with Lynch syndrome and Lynch-related cancers (PMIDs: 28888541 (2017), 28514183 (2017), 25980754 (2015)). Based on the available information, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Feb 08, 2022	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 in large population cohorts (gnomAD); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Observed in patients with Lynch-related cancers (Yurgelun 2015); This variant is associated with the following publications: (PMID: 28514183, 25980754, 32719484) -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 04, 2022	The c.2906_2907delAT pathogenic mutation, located in coding exon 4 of the MSH6 gene, results from a deletion of two nucleotides at nucleotide positions 2906 to 2907, causing a translational frameshift with a predicted alternate stop codon (p.Y969Lfs*5). This pathogenic mutation was identified in a cohort of 1260 individuals undergoing panel testing for Lynch syndrome due to having a diagnosis of a Lynch-associated cancer and/or polyps (Yurgelun MB et al. Gastroenterology, 2015 Sep;149:604-13.e20). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the 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. -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 29, 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 (PMID: 25980754, 33693762). 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. -

Lynch syndrome 5 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Aug 21, 2023

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

Lynch syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jun 08, 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 (PMID: 25980754, 33693762). 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. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 18, 2023

This sequence change creates a premature translational stop signal (p.Tyr969Leufs*5) 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 clinical features of Lynch syndrome (PMID: 25980754, 28514183). ClinVar contains an entry for this variant (Variation ID: 187691). For these reasons, this variant has been classified as Pathogenic. -

Endometrial carcinoma Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Jan 08, 2024

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Computational scores

Source: dbNSFP v4.3

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: rs786203924; hg19: chr2-48028026;