rs876658881

Positions:

• chr2-47799501-T-TA

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.1519dup​(p.Arg507LysfsTer9) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. D506D) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MSH6 NM_000179.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 3.58

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 2-47799501-T-TA is Pathogenic according to our data. Variant chr2-47799501-T-TA is described in ClinVar as [Pathogenic]. Clinvar id is 230978.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH6	NM_000179.3	c.1519dup	p.Arg507LysfsTer9	frameshift_variant	4/10	ENST00000234420.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH6	ENST00000234420.11	c.1519dup	p.Arg507LysfsTer9	frameshift_variant	4/10	1	NM_000179.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461874 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727236

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: 8.99e-7

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:4

Pathogenic, no assertion criteria provided	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	The MSH6 p.Arg507LysfsX9 variant was not identified in the literature. The variant was identified in the UMD database 1X as “causal”. The variant was not identified in the Clinvitae database, COSMIC, “Mismatch Repair Genes Variant Database”, “MMR Gene Unclassified Variants Database”, InSiGHT Colon Cancer Gene Variant Database, “Zhejiang Colon Cancer Database”, the ClinVar database, or GeneInsight COGR. The p.Arg507LysfsX9 duplication variant is predicted to cause a frameshift, which alters the protein's amino acid sequence beginning at codon 507 and leads to a premature stop codon 9 codons downstream. This alteration is then predicted to result in a truncated or absent protein and loss of function. Loss of function variants of the MSH6 gene are an established mechanism of disease in Lynch syndrome and this is the type of variant expected to cause the disorder. In summary, based on the above information, this variant meets our laboratory’s criteria to be classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Apr 14, 2019	The variant results in a shift of the reading frame, and is therefore predicted to result in the loss of a functional protein. Found in at least one symptomatic patient, and not found in general population data. -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Feb 06, 2024	- -

Lynch syndrome 5 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Aug 14, 2023

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

MSH6-related disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Oct 25, 2023

The MSH6 c.1519dupA variant is predicted to result in a frameshift and premature protein termination (p.Arg507Lysfs*9). This variant has been reported individuals with Lynch syndrome, colorectal cancer, breast cancer, and papillary thyroid cancer (see, for example, Table A1, Yurgelun et al. 2017. PubMed ID: 28135145; Rossi et al. 2017. PubMed ID: 28874130, Sandoval et al. 2021. PubMed ID: 33606809; Supplementary Table S4, Siraj et al. 2017. PubMed ID: 28975465). This variant has not been reported in a large population database (http://gnomad.broadinstitute.org), indicating it is rare. This variant is interpreted as pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/230978/). Frameshift variants in MSH6 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Oct 11, 2023

This sequence change creates a premature translational stop signal (p.Arg507Lysfs*9) 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 colorectal cancer or Lynch syndrome (PMID: 28135145, 28874130). ClinVar contains an entry for this variant (Variation ID: 230978). For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 08, 2023

The c.1519dupA pathogenic mutation, located in coding exon 4 of the MSH6 gene, results from a duplication of A at nucleotide position 1519, causing a translational frameshift with a predicted alternate stop codon (p.R507Kfs*9). This variant has been reported in multiple Lynch syndrome families (Yurgelun MB et al. J. Clin. Oncol., 2017 Apr;35:1086-1095; Siraj AK et al. Hum. Genet., 2017 11;136:1431-1444; Rossi BM et al. BMC Cancer, 2017 Sep;17:623). 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. -

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: rs876658881; hg19: chr2-48026640;