12-132676632-C-G

Position:

• chr12-132676632-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_006231.4(POLE):​c.823G>C​(p.Asp275His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,460,924 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: POLE NM_006231.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4 O:1
• Conservation: PhyloP100: 7.87

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.949

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLE	NM_006231.4	c.823G>C	p.Asp275His	missense_variant	9/49	ENST00000320574.10	NP_006222.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLE	ENST00000320574.10	c.823G>C	p.Asp275His	missense_variant	9/49	1	NM_006231.4	ENSP00000322570.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460924 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726844

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Mar 15, 2022	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. ClinVar contains an entry for this variant (Variation ID: 246352). This variant has not been reported in the literature in individuals affected with POLE-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces aspartic acid, which is acidic and polar, with histidine, which is basic and polar, at codon 275 of the POLE protein (p.Asp275His). -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jan 26, 2016	This variant is denoted POLE c.823G>C at the cDNA level, p.Asp275His (D275H) at the protein level, and results in the change of an Aspartic Acid to a Histidine (GAC>CAC). This variant has not, to our knowledge, been published in the literature as pathogenic or benign, although the Asp275 residue has been identified as important for metal ion binding, a necessary step in the catalytic reaction required for exonuclease activity (Derbyshire 1988). Functional assays interrogating a double mutant including a different amino acid alteration at this residue, POLE Asp275Ala, in combination with Glu277Ala, found significantly increased spontaneous mutation rates and loss of exonuclease activity when introduced in human and mouse cells as well as yeast and E. coli (Morrison 1991, Albertson 2009, Agbor 2013). Additionally the prokaryotic corollary of Asp275Ala demonstrated similar results when analyzed in the Phi-29 phage (Bernad 1989). However, to our knowledge, such functional studies have not been performed to interrogate POLE Asp275His.POLE Asp275His was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, suggesting it is not a common benign variant in these populations. Since Aspartic Acid and Histidine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. POLE Asp275His occurs at a position that is conserved across species and is located within motif I of the exonuclease domain (Preston 2010). In silico analyses predict that this variant is probably damaging to protein structure and function. Although this variant occurs at a residue likely to be functionally important, based on currently available evidence we consider POLE Asp275His to be a variant of uncertain significance. -

POLE-related disorder Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 29, 2024

The POLE c.823G>C variant is predicted to result in the amino acid substitution p.Asp275His. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. In ClinVar, this variant is interpreted as uncertain (https://preview.ncbi.nlm.nih.gov/clinvar/variation/246352/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 08, 2023

The p.D275H variant (also known as c.823G>C), located in coding exon 9 of the POLE gene, results from a G to C substitution at nucleotide position 823. The aspartic acid at codon 275 is replaced by histidine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Neoplasm Other:1

-, criteria provided, single submitter

clinical testing

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Jul 31, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.63	D;.
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D
M_CAP	Benign	0.082	D
MetaRNN	Pathogenic	0.95	D;D
MetaSVM	Uncertain	0.60	D
MutationAssessor	Pathogenic	3.3	M;.
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-6.3	D;D
REVEL	Pathogenic	0.73
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.98
MutPred		0.83		Gain of catalytic residue at E277 (P = 9e-04);.;
MVP		0.59
MPC		0.85
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.6
Varity_R		0.92
gMVP		0.91

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: rs879254218; hg19: chr12-133253218;