2-47806641-C-T

Variant names:

• chr2-47806641-C-T
• rs267608094
• NM_000179.3:c.3991C>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1_Strong PS3 PM2 PP5_Very_Strong

The NM_000179.3(MSH6):​c.3991C>T​(p.Arg1331*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000249 in 1,608,208 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★★). ClinVar reports functional evidence for this variant: "SCV000058973: studies have demonstrated that the variant results in skipping of exon 9, giving rise to a truncated mRNA leading to drastically reduced MSH6 protein levels, suggesting that this truncated protein is unstable (Plaschke 2006 PMID:16418736)." and additional evidence is available in ClinVar. Synonymous variant affecting the same amino acid position (i.e. R1331R) has been classified as Likely benign. The gene MSH6 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: MSH6 NM_000179.3 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:26
• Conservation: PhyloP100: 0.803
• Publications: 21 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]

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]

FBXO11 Gene-Disease associations (from GenCC):

• intellectual developmental disorder with dysmorphic facies and behavioral abnormalities

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Specifications for MSH6 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 15 pathogenic variants in the truncated region.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV000058973: studies have demonstrated that the variant results in skipping of exon 9, giving rise to a truncated mRNA leading to drastically reduced MSH6 protein levels, suggesting that this truncated protein is unstable (Plaschke 2006 PMID:16418736).; SCV004019084: Functional studies indicate this variant impacts protein function [PMID:16418736].; SCV000283835: Experimental studies have shown that this premature translational stop signal affects MSH6 function (PMID: 16418736).; SCV000695906: The variant has, however, also been reported in seemingly healthy individuals, including the father of a compound heterozygote child with Lynch Syndrome, indicating that it may exhibit reduced penetrance (Plaschke_2006). One publication reports experimental evidence indicating that the variant results in exon 9 skipping (Plaschke_2006), and multiple publications report a reduction of IHC staining for MSH6 protein in samples from individuals with this variant. Six ClinVar submissions from clinical diagnostic laboratories (evaluation after 2014) cite the variant as pathogenic. Plaschke_2006
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-47806641-C-T is Pathogenic according to our data. Variant chr2-47806641-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 42472.Status of the report is reviewed_by_expert_panel, 3 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000179.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MSH6	NM_000179.3	MANE Select	c.3991C>T	p.Arg1331*	stop_gained	Exon 9 of 10	NP_000170.1	P52701-1
	MSH6	NM_001406795.1		c.4087C>T	p.Arg1363*	stop_gained	Exon 10 of 11	NP_001393724.1
	MSH6	NM_001406813.1		c.3997C>T	p.Arg1333*	stop_gained	Exon 9 of 10	NP_001393742.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MSH6	ENST00000234420.11	TSL:1 MANE Select	c.3991C>T	p.Arg1331*	stop_gained	Exon 9 of 10	ENSP00000234420.5	P52701-1
	MSH6	ENST00000445503.5	TSL:1	n.*3338C>T		non_coding_transcript_exon	Exon 8 of 9	ENSP00000405294.1	F8WAX8
	MSH6	ENST00000445503.5	TSL:1	n.*3338C>T		3_prime_UTR	Exon 8 of 9	ENSP00000405294.1	F8WAX8

Frequencies

GnomAD3 genomes AF: 0.00000663 AC: 1 AN: 150928 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000407 AC: 1 AN: 245746 AF XY: 0.00000751

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1457280 Hom.: 0 Cov.: 35 AF XY: 0.00000276 AC XY: 2 AN XY: 725140

African (AFR) AF: 0.00 AC: 0 AN: 33420

American (AMR) AF: 0.00 AC: 0 AN: 44684

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.00 AC: 0 AN: 39660

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86188

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50530

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1110604

Other (OTH) AF: 0.00 AC: 0 AN: 60312

GnomAD4 genome AF: 0.00000663 AC: 1 AN: 150928 Hom.: 0 Cov.: 32 AF XY: 0.0000136 AC XY: 1 AN XY: 73588

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 40974

American (AMR) AF: 0.00 AC: 0 AN: 15100

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3464

East Asian (EAS) AF: 0.00 AC: 0 AN: 5156

South Asian (SAS) AF: 0.00 AC: 0 AN: 4790

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10242

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 312

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67908

Other (OTH) AF: 0.00 AC: 0 AN: 2070

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00000441 Hom.: 0

Bravo AF: 0.0000340

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
8	-	-	Lynch syndrome 5 (8)
7	-	-	not provided (7)
3	-	-	Lynch syndrome (3)
2	-	-	Hereditary cancer-predisposing syndrome (2)
1	-	-	Breast and/or ovarian cancer (1)
1	-	-	Endometrial carcinoma (1)
1	-	-	Endometrial carcinoma;C1833477:Lynch syndrome 5;C5436807:Mismatch repair cancer syndrome 3 (1)
1	-	-	Hereditary nonpolyposis colon cancer (1)
1	-	-	Hereditary nonpolyposis colorectal neoplasms (1)
1	-	-	MSH6-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	40
DANN	Uncertain	1.0
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.88	D
PhyloP100		0.80
Vest4		0.88
GERP RS		4.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=3/197	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		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: rs267608094; hg19: chr2-48033780; COSMIC: COSV52278149; COSMIC: COSV52278149;