2-47445660-A-G

Position:

• chr2-47445660-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000251.3(MSH2):​c.1386+3A>G variant causes a splice donor region, intron change. The variant allele was found at a frequency of 0.00000355 in 1,409,964 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: 33)
  • Exomes 𝑓: 0.0000035 (0 hom.)
• Consequence: MSH2 NM_000251.3 splice_donor_region, intron
• Scores: Splicing: ADA: 0.9780
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.78

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.1386+3A>G		splice_donor_region_variant, intron_variant		ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1386+3A>G		splice_donor_region_variant, intron_variant		1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000402 AC: 1 AN: 248984 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 134790

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: 0.0000333

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000355 AC: 5 AN: 1409964 Hom.: 0 Cov.: 24 AF XY: 0.00000284 AC XY: 2 AN XY: 704870

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: 0.0000473

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.38e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 12, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 30, 2023	The c.1386+3A>G intronic variant results from an A to G substitution 3 nucleotides after coding exon 8 in the MSH2 gene. This alteration was detected in 1 of 708 cases with a personal and/or family history of breast or ovarian cancer (Castéra L et al. Eur J Hum Genet. 2014 Feb). This alteration has been detected in several individuals who do not have a personal or family history that is consistent with or suggestive of hereditary nonpolyposis colorectal cancer (HNPCC)/Lynch syndrome (Ambry internal data). This nucleotide position is well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing; however, RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). Since supporting evidence is conflicting at this time, the clinical significance of this alteration remains unclear. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 26, 2023

This sequence change falls in intron 8 of the MSH2 gene. It does not directly change the encoded amino acid sequence of the MSH2 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs746390631, gnomAD 0.003%). This variant has been observed in individual(s) with hereditary breast and ovarian cancer syndrome (PMID: 24549055). ClinVar contains an entry for this variant (Variation ID: 185353). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Uncertain	23
DANN	Benign	0.91

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Pathogenic	0.84
SpliceAI score (max)		0.010		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: rs746390631; hg19: chr2-47672799;