rs1555793361

Variant names:

• chr19-50416529-G-A
• rs1555793361
• NM_002691.4:c.2953+1G>A

Your query was ambiguous. Multiple possible variants found:

• chr19-50416529-G-A
• chr19-50416529-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_002691.4(POLD1):​c.2953+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.000000714 in 1,400,194 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: POLD1 NM_002691.4 splice_donor, intron
• Scores: Splicing: ADA: 0.9998
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.13
• Publications: 0 publications found

Genes affected

POLD1 (HGNC:9175): (DNA polymerase delta 1, catalytic subunit) This gene encodes the 125-kDa catalytic subunit of DNA polymerase delta. DNA polymerase delta possesses both polymerase and 3' to 5' exonuclease activity and plays a critical role in DNA replication and repair. Alternatively spliced transcript variants have been observed for this gene, and a pseudogene of this gene is located on the long arm of chromosome 6. [provided by RefSeq, Mar 2012]

POLD1 Gene-Disease associations (from GenCC):

• POLD1-related polyposis and colorectal cancer syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• colorectal cancer, susceptibility to, 10

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
• mandibular hypoplasia-deafness-progeroid syndrome

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Genomics England PanelApp, Ambry Genetics, Orphanet, G2P
• Polymerase proofreading-related adenomatous polyposis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• immunodeficiency 120

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
• non-severe combined immunodeficiency due to polymerase delta deficiency

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ENSG00000142539 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLD1	NM_002691.4	c.2953+1G>A		splice_donor_variant, intron_variant	Intron 23 of 26	ENST00000440232.7	NP_002682.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7	c.2953+1G>A		splice_donor_variant, intron_variant	Intron 23 of 26	1	NM_002691.4	ENSP00000406046.1
ENSG00000142539	ENST00000599632.1	c.160+1G>A		splice_donor_variant, intron_variant	Intron 2 of 9	5		ENSP00000473233.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.14e-7 AC: 1 AN: 1400194 Hom.: 0 Cov.: 31 AF XY: 0.00000145 AC XY: 1 AN XY: 691416

African (AFR) AF: 0.00 AC: 0 AN: 31838

American (AMR) AF: 0.00 AC: 0 AN: 36386

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25172

East Asian (EAS) AF: 0.00 AC: 0 AN: 36080

South Asian (SAS) AF: 0.00 AC: 0 AN: 79592

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 45680

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5188

European-Non Finnish (NFE) AF: 9.24e-7 AC: 1 AN: 1082136

Other (OTH) AF: 0.00 AC: 0 AN: 58122

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Colorectal cancer, susceptibility to, 10 Uncertain:1

Aug 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 23 of the POLD1 gene. Missense variants that disrupt the 3'-5' exonuclease (proof-reading) activity of the POLD1 protein are associated with PPAP (polymerase proofreading–associated polyposis) (PMID: 23263490, 23447401). However, loss-of-function variants that result in an absent or severely disrupted POLD1 protein, and missense variants outside the exonuclease domain, are unlikely to be associated with PPAP. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with POLD1-related conditions. ClinVar contains an entry for this variant (Variation ID: 469313). Studies have shown that disruption of this splice site results in skipping of exon 23 and introduces a premature termination codon (internal data). The resulting mRNA is expected to undergo nonsense-mediated decay. 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

Dec 20, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2953+1G>A intronic variant results from a G to A substitution one nucleotide after coding exon 22 of the POLD1 gene. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. 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. However, loss of function of POLD1 has not been established as a mechanism of disease. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.070
CADD	Pathogenic	29
DANN	Uncertain	0.98
Eigen	Pathogenic	0.85
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.95	D
PhyloP100		7.1
GERP RS		2.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.85
SpliceAI score (max)		0.95		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.95		Position offset: -1

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

Other links and lift over

dbSNP: rs1555793361; hg19: chr19-50919786; COSMIC: COSV54529447;