2-47806859-A-T

Variant names:

• chr2-47806859-A-T
• rs907892681
• NM_000179.3:c.4082A>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PM4

The NM_000179.3(MSH6):​c.4082A>T​(p.Ter1361Leuext*?) variant causes a stop lost change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MSH6 NM_000179.3 stop_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.74
• Publications: 0 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: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Stoplost variant in NM_000179.3 Downstream stopcodon found after 1389 codons.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.4082A>T	p.Ter1361Leuext*?	stop_lost	Exon 10 of 10	ENST00000234420.11	NP_000170.1
FBXO11	NM_001190274.2	c.*1259T>A		downstream_gene_variant		ENST00000403359.8	NP_001177203.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.4082A>T	p.Ter1361Leuext*?	stop_lost	Exon 10 of 10	1	NM_000179.3	ENSP00000234420.5
FBXO11	ENST00000403359.8	c.*1259T>A		downstream_gene_variant		1	NM_001190274.2	ENSP00000384823.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Nov 09, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change disrupts the translational stop signal of the MSH6 mRNA. It is expected to extend the length of the MSH6 protein by 29 additional amino acid residues. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MSH6-related conditions. ClinVar contains an entry for this variant (Variation ID: 455322). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.46
CADD	Benign	18
DANN	Benign	0.87
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Uncertain	0.80	D
PhyloP100		3.7
Vest4		0.45
GERP RS		3.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Mutation Taster		=49/151	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.29		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.29		Position offset: 41

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

Other links and lift over

dbSNP: rs907892681; hg19: chr2-48033998;