2-47416374-C-T

Position:

• chr2-47416374-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 8P and 1B. PM1 PM2 PM5 PP3_Moderate BP6

The NM_000251.3(MSH2):​c.1021C>T​(p.Leu341Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,132 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. L341P) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 1.34

Genes affected

MSH2 (HGNC:7325): (mutS homolog 2) This locus is frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). When cloned, it was discovered to be a human homolog of the E. coli mismatch repair gene mutS, consistent with the characteristic alterations in microsatellite sequences (RER+ phenotype) found in HNPCC. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a helix (size 11) in uniprot entity MSH2_HUMAN there are 5 pathogenic changes around while only 1 benign (83%) in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-47416375-T-C is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.938
• BP6: Variant 2-47416374-C-T is Benign according to our data. Variant chr2-47416374-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 483696.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=1, Likely_benign=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1021C>T	p.Leu341Phe	missense_variant	6/16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1021C>T	p.Leu341Phe	missense_variant	6/16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251452 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135896

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460132 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726512

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 05, 2024

The p.L341F variant (also known as c.1021C>T), located in coding exon 6 of the MSH2 gene, results from a C to T substitution at nucleotide position 1021. The leucine at codon 341 is replaced by phenylalanine, an amino acid with highly similar properties. In a massively parallel cell-based functional assay testing susceptibility to a DNA damaging agent, 6-thioguanine (6-TG), this variant was determined to be functionally neutral (Jia X et al. Am J Hum Genet, 2021 Jan;108:163-175). 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 variant remains unclear. -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 24, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D;.;.;.
Eigen	Benign	0.064
Eigen_PC	Benign	0.0085
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Uncertain	0.97	D;D;D;D
M_CAP	Uncertain	0.17	D
MetaRNN	Pathogenic	0.94	D;D;D;D
MetaSVM	Uncertain	0.0039	D
MutationAssessor	Pathogenic	3.5	H;.;.;.
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-3.9	D;D;.;D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0020	D;D;.;D
Sift4G	Uncertain	0.0040	D;D;.;D
Polyphen		1.0	D;.;.;D
Vest4		0.74
MutPred		0.82		Loss of catalytic residue at L341 (P = 0.0651);.;Loss of catalytic residue at L341 (P = 0.0651);Loss of catalytic residue at L341 (P = 0.0651);
MVP		0.95
MPC		0.034
ClinPred		1.0	D
GERP RS		1.5
Varity_R		0.88
gMVP		0.57

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: rs748115066; hg19: chr2-47643513;