7-5991990-T-G

Variant names:

• chr7-5991990-T-G
• rs1554299388
• NM_000535.7:c.971A>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000535.7(PMS2):​c.971A>C​(p.Asn324Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N324K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.67
• Publications: 0 publications found

Genes affected

PMS2 (HGNC:9122): (PMS1 homolog 2, mismatch repair system component) The protein encoded by this gene is a key component of the mismatch repair system that functions to correct DNA mismatches and small insertions and deletions that can occur during DNA replication and homologous recombination. This protein forms heterodimers with the gene product of the mutL homolog 1 (MLH1) gene to form the MutL-alpha heterodimer. The MutL-alpha heterodimer possesses an endonucleolytic activity that is activated following recognition of mismatches and insertion/deletion loops by the MutS-alpha and MutS-beta heterodimers, and is necessary for removal of the mismatched DNA. There is a DQHA(X)2E(X)4E motif found at the C-terminus of the protein encoded by this gene that forms part of the active site of the nuclease. Mutations in this gene have been associated with hereditary nonpolyposis colorectal cancer (HNPCC; also known as Lynch syndrome) and Turcot syndrome. [provided by RefSeq, Apr 2016]

PMS2 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Lynch syndrome 4

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• mismatch repair cancer syndrome 4

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• ovarian cancer

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• Muir-Torre syndrome

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• breast cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• prostate cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.887

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000535.7. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PMS2	NM_000535.7	MANE Select	c.971A>C	p.Asn324Thr	missense	Exon 9 of 15	NP_000526.2
	PMS2	NM_001406866.1		c.1157A>C	p.Asn386Thr	missense	Exon 10 of 16	NP_001393795.1
	PMS2	NM_001322014.2		c.971A>C	p.Asn324Thr	missense	Exon 9 of 15	NP_001308943.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PMS2	ENST00000265849.12	TSL:1 MANE Select	c.971A>C	p.Asn324Thr	missense	Exon 9 of 15	ENSP00000265849.7
	PMS2	ENST00000406569.8	TSL:1	n.971A>C		non_coding_transcript_exon	Exon 9 of 13	ENSP00000514464.1
	PMS2	ENST00000382321.5	TSL:1	c.803+5336A>C		intron	N/A	ENSP00000371758.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 26

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Oct 13, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine with threonine at codon 324 of the PMS2 protein (p.Asn324Thr). The asparagine residue is moderately conserved and there is a small physicochemical difference between asparagine and threonine. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with PMS2-related disease. This variant is not present in population databases (ExAC no frequency).

Hereditary cancer-predisposing syndrome Uncertain:1

Jan 04, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.N324T variant (also known as c.971A>C), located in coding exon 9 of the PMS2 gene, results from an A to C substitution at nucleotide position 971. The asparagine at codon 324 is replaced by threonine, an amino acid with similar properties. This amino acid position is highly 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.38
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.070
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.65	D
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.92	D
M_CAP	Benign	0.058	D
MetaRNN	Pathogenic	0.89	D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Pathogenic	3.8	H
PhyloP100		7.7
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.72		Loss of catalytic residue at N324 (P = 0.1437)
MVP		0.96
MPC		0.27
ClinPred		0.99	D
GERP RS		5.4
Varity_R		0.93
gMVP		0.58
Mutation Taster		=27/73	disease causing

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

Other links and lift over

dbSNP: rs1554299388; hg19: chr7-6031621;