rs63751009

chr2-47799548-A-Gchr2-47799548-A-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP6

The NM_000179.3(MSH6):c.1565A>G(p.Gln522Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000752 in 1,461,864 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. Q522E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7 B:2 O:1
• Conservation: PhyloP100: 9.24

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 -1 ACMG points.

• BP6: Variant 2-47799548-A-G is Benign according to our data. Variant chr2-47799548-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 89200.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=7, not_provided=1, Likely_benign=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH6	NM_000179.3	c.1565A>G	p.Gln522Arg	missense_variant	4/10	ENST00000234420.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH6	ENST00000234420.11	c.1565A>G	p.Gln522Arg	missense_variant	4/10	1	NM_000179.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251306 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135814

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461864 Hom.: 0 Cov.: 34 AF XY: 0.0000110 AC XY: 8 AN XY: 727232

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000899

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7 Benign:2 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Oct 28, 2016	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 15, 2023	The p.Q522R variant (also known as c.1565A>G), located in coding exon 4 of the MSH6 gene, results from an A to G substitution at nucleotide position 1565. The glutamine at codon 522 is replaced by arginine, an amino acid with highly similar properties. This variant has been reported in multiple early-onset colorectal patients, including two whose tumors demonstrated intact MSH6 expression by IHC analysis (Berends MJ et al. Am. J. Hum. Genet. 2002 Jan; 70(1):26-37; Domingo E et al. Oncogene 2005 Jun; 24(24):3995-8; Niessen RC et al. Gut 2006 Dec; 55(12):1781-8). In an in vitro MMR assay, p.Q522R was classified as repair proficient due to its repair efficiency being significantly higher than repair-deficient controls (Drost M et al. Hum. Mutat. 2012 Mar; 33(3):488-94). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Dec 29, 2021	- -

Lynch syndrome 5 Uncertain:2 Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 30, 2023	This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
not provided, no classification provided	phenotyping only	GenomeConnect - Invitae Patient Insights Network	-	Variant interpreted as Likely benign and reported on 09-17-2020 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Oct 16, 2017	- -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Oct 10, 2019

Variant summary: MSH6 c.1565A>G (p.Gln522Arg) results in a conservative amino acid change located in the DNA mismatch repair protein MutS-like, N-terminal domain (IPR007695). Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251306 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1565A>G has been reported in the literature in at least 3 individuals affected with colorectal cancer, however the associated tumors in 2 of these cases were noted to be microsatellite stable (Berends_2002, Domingo_2005). These reports therefore do not provide unequivocal conclusions about association of the variant with Lynch Syndrome. Experimental evidence evaluating an impact on protein function demonstrated the variant protein has a repair efficiency that was significantly higher than repair-deficient controls (~75% of the wild-type), therefore was concluded to be repair proficient in this assay (Drost_2012). Five ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance (4x) or likely benign (1x). Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Apr 04, 2023

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Observed in at least four cases of early-onset colorectal cancers, most exhibiting normal MSI and/or IHC analyses, with no corresponding family having met Amsterdam I or II criteria for Lynch Syndrome (Berends et al., 2002; Domingo et al., 2005; Niessen et al., 2006); This variant is associated with the following publications: (PMID: 26333163, 11709755, 15782118, 24100870, 16636019, 18790734, 17531815, 21120944, 22102614) -

Endometrial carcinoma Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

May 28, 2023

- -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Dec 19, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.32
Cadd	Benign	22
Dann	Uncertain	0.99
Eigen	Benign	-0.10
Eigen_PC	Benign	0.12
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Uncertain	0.14	D
MetaRNN	Uncertain	0.70	D;D;D;D;D
MetaSVM	Uncertain	-0.27	T
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.71	T
Sift4G	Benign	0.79	T;T;T;T;T
Polyphen		0.083	.;.;B;.;.
Vest4		0.87
MutPred		0.72		.;.;Gain of MoRF binding (P = 0.0298);.;.;
MVP		0.93
ClinPred		0.40	T
GERP RS		5.2
Varity_R		0.52
gMVP		0.75

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs63751009; hg19: chr2-48026687;