rs773262801

Variant names:

• chr2-47805636-T-TTGAA
• rs773262801
• NM_000179.3:c.3577_3580dupGAAT

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.3577_3580dupGAAT​(p.Leu1194fs) variant causes a frameshift, stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: MSH6 NM_000179.3 frameshift, stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 0.904

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 2-47805636-T-TTGAA is Pathogenic according to our data. Variant chr2-47805636-T-TTGAA is described in ClinVar as [Pathogenic]. Clinvar id is 455271.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.3577_3580dupGAAT	p.Leu1194fs	frameshift_variant, stop_gained	Exon 7 of 10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.3577_3580dupGAAT	p.Leu1194fs	frameshift_variant, stop_gained	Exon 7 of 10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251392 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135860

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Lynch syndrome 5 Pathogenic:1

Jul 12, 2023

Myriad Genetics, Inc.

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Sep 03, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

While this particular variant has not been reported in the literature, loss-of-function variants in MSH6 are known to be pathogenic (PMID: 24362816, 18269114). This sequence change inserts 4 nucleotides in exon 7 of the MSH6 mRNA (c.3577_3580dupGAAT), causing a frameshift at codon 1194. This creates a premature translational stop signal (p.Leu1194*) and is expected to result in an absent or disrupted protein product. For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Apr 26, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3577_3580dupGAAT pathogenic mutation, located in coding exon 7 of the MSH6 gene, results from a duplication of GAAT at nucleotide position 3577, causing a translational frameshift with a predicted alternate stop codon (p.L1194*). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). 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

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs773262801; hg19: chr2-48032775;