rs374597395

chr2-47783381-T-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_Moderate BP6

The NM_000179.3(MSH6):c.148T>C(p.Trp50Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000417 in 1,439,662 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 10/13 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. W50C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000042 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:4
• Conservation: PhyloP100: -0.315

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]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.12155649).
• BP6: Variant 2-47783381-T-C is Benign according to our data. Variant chr2-47783381-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 187071.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH6	NM_000179.3	c.148T>C	p.Trp50Arg	missense_variant	1/10	ENST00000234420.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH6	ENST00000234420.11	c.148T>C	p.Trp50Arg	missense_variant	1/10	1	NM_000179.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000991 AC: 2 AN: 201732 Hom.: 0 AF XY: 0.0000179 AC XY: 2 AN XY: 111908

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000235

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000417 AC: 6 AN: 1439662 Hom.: 0 Cov.: 32 AF XY: 0.00000560 AC XY: 4 AN XY: 714692

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000454

Gnomad4 OTH exome AF: 0.0000168

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000130 AC: 1

ExAC AF: 0.00000868 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Lynch syndrome Uncertain:1 Benign:1

Uncertain significance, no assertion criteria provided	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	The MSH6 p.Trp50Arg variant was not identified in the literature nor was it identified in the GeneInsight-COGR, Cosmic, MutDB, Zhejiang University Database, Mismatch Repair Genes Variant Database, MMR Gene Unclassified Variants Database, or Insight Hereditary Tumors databases. The variant was identified in dbSNP (ID: rs374597395) as "With Likely benign allele", ClinVar (classified as likely benign by Ambry Genetics and Invitae), and in UMD-LSDB (1x) databases. The variant was identified in control databases in 2 of 199148 chromosomes at a frequency of 0.00001 (Genome Aggregation Database Feb 27, 2017). The variant identified in European population in 2 of 84074 chromosomes (freq: 0.00002), while the variant was not observed in the African, Other, Latino, Ashkenazi Jewish, East Asian, Finnish, and South Asian populations. The p.Trp50 residue is not conserved in mammals and four out of five 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, HumanSpliceFinder) 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. -
Likely benign, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Sep 17, 2023	- -

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 25, 2018	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 29, 2019	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Jul 11, 2022

Variant summary: MSH6 c.148T>C (p.Trp50Arg) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. A bioinformatics analysis supports that this missense variant does not alter protein structure (example: Terui_2013). The variant allele was found at a frequency of 9.9e-06 in 201732 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.148T>C in individuals affected with Lynch Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant VUS (n=1) and likely benign (n=3). 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

May 08, 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; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 23621914) -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Dec 14, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.26	T
BayesDel_noAF	Benign	-0.34
Cadd	Benign	15
Dann	Benign	0.72
DEOGEN2	Benign	0.067	T
Eigen	Benign	-1.1
Eigen_PC	Benign	-0.99
FATHMM_MKL	Benign	0.011	N
LIST_S2	Benign	0.20	T
M_CAP	Pathogenic	0.54	D
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-0.75	T
MutationTaster	Benign	0.88	N;N
Sift4G	Benign	0.32	T
Vest4		0.28
MVP		0.48
ClinPred		0.037	T
GERP RS		-2.6
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.7

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: rs374597395; hg19: chr2-48010520;