rs779830137

Variant names:

• chr12-132663998-ACTCAC-A
• rs779830137
• NM_006231.4:c.2706+1_2706+5delGTGAG

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_006231.4(POLE):​c.2706+1_2706+5delGTGAG variant causes a splice donor, splice region, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,524 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: POLE NM_006231.4 splice_donor, splice_region, intron
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 7.85
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• POLE-related polyposis and colorectal cancer syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• colorectal cancer, susceptibility to, 12

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
• facial dysmorphism-immunodeficiency-livedo-short stature syndrome

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
• intrauterine growth retardation, metaphyseal dysplasia, adrenal hypoplasia congenita, genital anomalies, and immunodeficiency

  Inheritance: AR Classification: STRONG Submitted by: G2P
• IMAGe syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Polymerase proofreading-related adenomatous polyposis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-132663998-ACTCAC-A is Pathogenic according to our data. Variant chr12-132663998-ACTCAC-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 540797.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLE	NM_006231.4	c.2706+1_2706+5delGTGAG		splice_donor_variant, splice_region_variant, intron_variant	Intron 23 of 48	ENST00000320574.10	NP_006222.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLE	ENST00000320574.10	c.2706+1_2706+5delGTGAG		splice_donor_variant, splice_region_variant, intron_variant	Intron 23 of 48	1	NM_006231.4	ENSP00000322570.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251384 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461524 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 727076

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86232

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5486

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111998

Other (OTH) AF: 0.00 AC: 0 AN: 60368

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

Jan 23, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a splice site in intron 23 of the POLE gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in POLE are known to be pathogenic (PMID: 23230001, 25948378, 30503519). This variant is present in population databases (rs779830137, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with POLE-related conditions. ClinVar contains an entry for this variant (Variation ID: 540797). 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 currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Hereditary cancer-predisposing syndrome Uncertain:1

Dec 17, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2706+1_2706+5delGTGAG intronic variant results from a deletion of 5 nucleotides between positions 2706+1 and 2706+5 and involves the canonical splice donor site after coding exon 23 of the POLE gene. This nucleotide region is well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. Loss-of-function variants subject to nonsense mediated decay (NMD) in POLE are known to cause POLE deficiency; however, such associations with POLE-related polymerase proofreading-associated polyposis (PPAP) have not been reported. Based on the supporting evidence, this alteration is likely pathogenic for POLE deficiency; however, the association of this alteration with POLE-related polymerase proofreading-associated polyposis (PPAP) is unknown. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.8
Mutation Taster		=21/79	disease causing

Splicing

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

Other links and lift over

dbSNP: rs779830137; hg19: chr12-133240584;