chr12-132624994-C-A

Position:

• chr12-132624994-C-A

Variant summary

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

The NM_006231.4(POLE):​c.6658G>T​(p.Val2220Phe) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/25 in silico tools predict a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: POLE NM_006231.4 missense, splice_region
• Scores: Splicing: ADA: 0.2744
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.161

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 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=0.3038637).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLE	NM_006231.4	c.6658G>T	p.Val2220Phe	missense_variant, splice_region_variant	48/49	ENST00000320574.10	NP_006222.2
POLE	XM_011534795.4	c.*186G>T		downstream_gene_variant			XP_011533097.1
POLE	XM_011534797.4	c.*186G>T		downstream_gene_variant			XP_011533099.1
POLE	XM_011534802.4	c.*186G>T		downstream_gene_variant			XP_011533104.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLE	ENST00000320574.10	c.6658G>T	p.Val2220Phe	missense_variant, splice_region_variant	48/49	1	NM_006231.4	ENSP00000322570.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 19, 2022

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 valine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 2220 of the POLE protein (p.Val2220Phe). ClinVar contains an entry for this variant (Variation ID: 405674). 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 tolerated. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 16, 2024

The p.V2220F variant (also known as c.6658G>T) is located in coding exon 48 of the POLE gene. The valine at codon 2220 is replaced by phenylalanine, an amino acid with highly similar properties. This change occurs in the first base pair of coding exon 48. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.099
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.44
CADD	Benign	2.3
DANN	Benign	0.96
DEOGEN2	Benign	0.23	T;.
Eigen	Benign	-1.2
Eigen_PC	Benign	-1.3
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.30	T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Uncertain	2.4	M;.
PrimateAI	Benign	0.25	T
PROVEAN	Benign	-1.6	N;N
REVEL	Benign	0.16
Sift	Benign	0.048	D;D
Sift4G	Uncertain	0.051	T;T
Polyphen		0.22	B;.
Vest4		0.54
MutPred		0.31		Gain of catalytic residue at L2222 (P = 0.0024);.;
MVP		0.055
MPC		0.29
ClinPred		0.19	T
GERP RS		-5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.20
gMVP		0.43

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.27
dbscSNV1_RF	Benign	0.40
SpliceAI score (max)		0.24		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.24		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060500804; hg19: chr12-133201580;