chr12-132687313-C-T

Variant names:

• chr12-132687313-C-T
• rs1555231433
• NM_006231.4:c.3G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PVS1_Moderate PS1_Moderate PM2 PP5

The NM_006231.4(POLE):​c.3G>A​(p.Met1?) variant causes a start lost change involving the alteration of a non-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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: POLE NM_006231.4 start_lost
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 0.991

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PVS1: Start lost variant, next in-frame start position is after 2 pathogenic variants. Next in-frame start position is after 44 codons. Genomic position: 132681212. Lost 0.019 part of the original CDS.
• PS1: Another start lost variant in NM_006231.4 (POLE) was described as [Pathogenic] in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-132687313-C-T is Pathogenic according to our data. Variant chr12-132687313-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 540655.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLE	NM_006231.4	c.3G>A	p.Met1?	start_lost	Exon 1 of 49	ENST00000320574.10	NP_006222.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLE	ENST00000320574.10	c.3G>A	p.Met1?	start_lost	Exon 1 of 49	1	NM_006231.4	ENSP00000322570.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1349712 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 666002

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1

Apr 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects the initiator methionine of the POLE mRNA. The next in-frame methionine is located at codon 44. This variant is not present in population databases (gnomAD no frequency). Disruption of the initiator codon has been observed in individual(s) with clinical features of autosomal recessive FILS syndrome (PMID: 30503519). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 540655). For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Uncertain:1

Oct 25, 2017

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.M1? variant (also known as c.3G>A), located in coding exon 1 of the POLE gene, results from a G to A substitution at nucleotide position 3. This alters the methionine residue at the initiation codon. However, there exists a possible alternate initiation site just 43 residues downstream. This amino acid position is well conserved on limited sequence alignment. Variations that modify the initiation codon (ATG) are expected to result in either loss of translation initiation or N-terminal truncation. However, 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.040
CADD	Benign	21
DANN	Benign	0.95
DEOGEN2	Benign	0.12	T;.
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.65
FATHMM_MKL	Benign	0.033	N
LIST_S2	Uncertain	0.90	D;D
M_CAP	Pathogenic	0.71	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Benign	-0.99	T
PROVEAN	Benign	-2.0	N;N
REVEL	Benign	0.26
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.0	B;B
Vest4		0.71
MutPred		0.88		Gain of catalytic residue at R4 (P = 0.0169);Gain of catalytic residue at R4 (P = 0.0169);
MVP		0.32
ClinPred		0.75	D
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.92
gMVP		0.61

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: rs1555231433; hg19: chr12-133263899;