chr12-132668813-G-A

Position:

• chr12-132668813-G-A

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_006231.4(POLE):​c.1921C>T​(p.Gln641*) variant causes a stop gained, splice region 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: POLE NM_006231.4 stop_gained, splice_region
• Scores: Splicing: ADA: 0.9985
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 10.0

Genes affected

POLE (HGNC:9177): (DNA polymerase epsilon, catalytic subunit) This gene encodes the catalytic subunit of DNA polymerase epsilon. The enzyme is involved in DNA repair and chromosomal DNA replication. Mutations in this gene have been associated with colorectal cancer 12 and facial dysmorphism, immunodeficiency, livedo, and short stature. [provided by RefSeq, Sep 2013]

POLE (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-132668813-G-A is Pathogenic according to our data. Variant chr12-132668813-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 405587.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLE	NM_006231.4	c.1921C>T	p.Gln641*	stop_gained, splice_region_variant	17/49	ENST00000320574.10	NP_006222.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLE	ENST00000320574.10	c.1921C>T	p.Gln641*	stop_gained, splice_region_variant	17/49	1	NM_006231.4	ENSP00000322570.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 11, 2022

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 405587). This sequence change creates a premature translational stop signal (p.Gln641*) in the POLE gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in POLE are known to be pathogenic (PMID: 23230001, 25948378, 30503519). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with POLE-related conditions. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 13, 2015

The p.Q641* variant (also known as c.1921C>T), located in coding exon 17 of the POLE gene, results from a C to T substitution at nucleotide position 1921. This changes the amino acid from a glutamine to a stop codon within coding exon 17. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. As neither this specific alteration nor loss of function as a mechanism of pathogenicity have been well-described in the POLE gene, the clinical significance of this variant remains unknown (ACMG Standards and guidelines for the interpretation of sequence variants. Genet Med. 2015 May;17(5):405-23). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	59
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
Vest4		0.96
GERP RS		5.7
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		3.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.90
SpliceAI score (max)		0.80		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.80		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1060500777; hg19: chr12-133245399;