rs115386788

chr2-47800946-G-Achr2-47800946-G-Cchr2-47800946-G-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_000179.3(MSH6):c.2963G>A(p.Arg988His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000261 in 1,571,572 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign 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. R988L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000025 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:1
• Conservation: PhyloP100: 2.37

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 Likely_benign. Variant got -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.10481465).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH6	NM_000179.3	c.2963G>A	p.Arg988His	missense_variant	4/10	ENST00000234420.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH6	ENST00000234420.11	c.2963G>A	p.Arg988His	missense_variant	4/10	1	NM_000179.3	P4

Frequencies

GnomAD3 genomes AF: 0.0000394 AC: 6 AN: 152154 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000621

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000507 AC: 11 AN: 217126 Hom.: 0 AF XY: 0.0000601 AC XY: 7 AN XY: 116510

Gnomad AFR exome AF: 0.0000633

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000403

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000978

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000247 AC: 35 AN: 1419418 Hom.: 0 Cov.: 34 AF XY: 0.0000385 AC XY: 27 AN XY: 701986

Gnomad4 AFR exome AF: 0.0000630

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000355

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000183

Gnomad4 OTH exome AF: 0.0000342

GnomAD4 genome AF: 0.0000394 AC: 6 AN: 152154 Hom.: 0 Cov.: 32 AF XY: 0.0000673 AC XY: 5 AN XY: 74314

Gnomad4 AFR AF: 0.0000483

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000621

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000243 Hom.: 0

Bravo AF: 0.0000302

ExAC AF: 0.0000659 AC: 8

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 26, 2023	The p.R988H variant (also known as c.2963G>A), located in coding exon 4 of the MSH6 gene, results from a G to A substitution at nucleotide position 2963. The arginine at codon 988 is replaced by histidine, an amino acid with highly similar properties. This variant was also observed in 1/3251 individuals who met eligibility criteria for hereditary breast and ovarian cancer syndrome (Lerner-Ellis J et al. J Cancer Res Clin Oncol, 2021 Mar;147:871-879). This amino acid position is not well conserved in available vertebrate species, and histidine is the reference amino acid in other vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Sep 27, 2023	This missense variant replaces arginine with histidine at codon 988 of the MSH6 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with endometrial cancer (PMID: 32885271). This variant has been identified in 11/217126 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Lynch syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Feb 05, 2024

This missense variant replaces arginine with histidine at codon 988 of the MSH6 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 11/217126 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 26, 2020

Has not been previously published as a germline pathogenic or benign variant to our knowledge; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 28912153, 30798936) -

Endometrial carcinoma Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The MSH6 p.Arg988His variant was not identified in the literature nor was it identified in the COGR, MutDB, UMD-LSDB, Zhejiang University Database, Mismatch Repair Genes Variant Database, or Insight Hereditary Tumors database. The variant was identified in dbSNP (ID: rs115386788) as "With Uncertain significance allele”, ClinVar (classified as uncertain significance by Invitae, GeneDx and Ambry Genetics), and in Cosmic (1x in prostate tissue) database. The variant was identified in 11 of 212122 chromosomes at a frequency of 0.00005 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: African in 1 of 14826 chromosomes (freq: 0.00007), European in 1 of 99952 chromosomes (freq: 0.00001), and South Asian in 9 of 22466 chromosomes (freq: 0.0004); it was not observed in the Other, Latino, Ashkenazi Jewish, East Asian, or Finnish populations. The p.Arg988 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein; however, this information is not predictive enough to rule out pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Dec 09, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.089
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.17
Cadd	Benign	17
Dann	Uncertain	0.97
Eigen	Benign	-0.58
Eigen_PC	Benign	-0.54
FATHMM_MKL	Uncertain	0.90	D
M_CAP	Benign	0.041	D
MetaRNN	Benign	0.10	T;T;T;T;T
MetaSVM	Benign	-0.35	T
MutationTaster	Benign	1.0	N;N;N;N
PrimateAI	Benign	0.24	T
Sift4G	Uncertain	0.040	D;D;D;T;D
Polyphen		0.0060	.;.;B;.;.
Vest4		0.29
MVP		0.86
ClinPred		0.076	T
GERP RS		0.14
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.31
gMVP		0.50

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: rs115386788; hg19: chr2-48028085; COSMIC: COSV52274524; COSMIC: COSV52274524;