2-47478481-C-T

Position:

• chr2-47478481-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000251.3(MSH2):​c.2420C>T​(p.Thr807Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,806 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.18

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]

MSH2 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.39119095).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH2	NM_000251.3	c.2420C>T	p.Thr807Ile	missense_variant	14/16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.2420C>T	p.Thr807Ile	missense_variant	14/16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251378 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135856

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461806 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727194

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Apr 09, 2015

This variant is denoted MSH2 c.2420C>T at the cDNA level, p.Thr807Ile (T807I) at the protein level, and results in the change of a Threonine to an Isoleucine (ACT>ATT). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. MSH2 Thr807Ile was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Since Threonine and Isoleucine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. MSH2 Thr807Ile occurs at a position that is moderately conserved across species and is located in the ATPase domain (Lutzen 2008). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available information, it is unclear whether MSH2 Thr807Ile is pathogenic or benign. We consider it to be a variant of uncertain significance. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 23, 2020

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MSH2 protein function. This variant has not been reported in the literature in individuals with MSH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 418859). This variant is present in population databases (rs41295294, ExAC 0.001%). This sequence change replaces threonine with isoleucine at codon 807 of the MSH2 protein (p.Thr807Ile). The threonine residue is moderately conserved and there is a moderate physicochemical difference between threonine and isoleucine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 01, 2023

The p.T807I variant (also known as c.2420C>T), located in coding exon 14 of the MSH2 gene, results from a C to T substitution at nucleotide position 2420. The threonine at codon 807 is replaced by isoleucine, an amino acid with similar properties. In a massively parallel cell-based functional assay testing susceptibility to a DNA damaging agent, 6-thioguanine (6-TG), this variant was reported to be functionally neutral (Jia X et al. Am J Hum Genet, 2021 Jan;108:163-175). This amino acid position is not well conserved in available 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.71	D;.;.;.
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Benign	0.077	D
MetaRNN	Benign	0.39	T;T;T;T
MetaSVM	Uncertain	0.45	D
MutationAssessor	Benign	0.60	N;.;.;.
PrimateAI	Uncertain	0.61	T
PROVEAN	Uncertain	-3.2	D;D;.;D
REVEL	Uncertain	0.45
Sift	Uncertain	0.021	D;D;.;D
Sift4G	Uncertain	0.036	D;D;.;D
Polyphen		0.62	P;.;.;P
Vest4		0.49
MutPred		0.36		Loss of disorder (P = 0.0524);.;Loss of disorder (P = 0.0524);Loss of disorder (P = 0.0524);
MVP		0.88
MPC		0.021
ClinPred		0.81	D
GERP RS		4.4
Varity_R		0.34
gMVP		0.63

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: rs41295294; hg19: chr2-47705620;