chr2-47799680-G-C

Variant names:

• chr2-47799680-G-C
• rs758990693
• NM_000179.3:c.1697G>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM2 PP3_Strong BP6

The NM_000179.3(MSH6):​c.1697G>C​(p.Gly566Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,886 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G566R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 8.07
• Publications: 3 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 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984
• BP6: Variant 2-47799680-G-C is Benign according to our data. Variant chr2-47799680-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 937933.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.1697G>C	p.Gly566Ala	missense_variant	Exon 4 of 10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.1697G>C	p.Gly566Ala	missense_variant	Exon 4 of 10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 250304 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00000137 AC: 2 AN: 1461886 Hom.: 0 Cov.: 34 AF XY: 0.00000275 AC XY: 2 AN XY: 727242

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

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Mar 19, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G566A variant (also known as c.1697G>C), located in coding exon 4 of the MSH6 gene, results from a G to C substitution at nucleotide position 1697. The glycine at codon 566 is replaced by alanine, an amino acid with similar properties. This variant was detected in 0% of 1292 individuals with biliary tract cancer and 0.001% of 37583 controls without a personal or family history of cancer (Okawa Y et al. J Hepatol, 2023 Feb;78:333-342). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Dec 16, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.58
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.43
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.87	.;.;D;T;.
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	.;D;D;D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Uncertain	0.54	D
MutationAssessor	Uncertain	2.8	.;.;M;.;.
PhyloP100		8.1
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-5.1	.;D;D;.;D
REVEL	Pathogenic	0.84
Sift	Pathogenic	0.0	.;D;D;.;D
Sift4G	Benign	0.12	T;D;D;T;T
Polyphen		1.0	.;.;D;.;.
Vest4		0.95
MutPred		0.94		.;.;Gain of catalytic residue at G566 (P = 0.0419);.;.;
MVP		0.95
ClinPred		0.98	D
GERP RS		4.5
Varity_R		0.96
gMVP		0.78
Mutation Taster		=34/66	disease causing

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

Other links and lift over

dbSNP: rs758990693; hg19: chr2-48026819;