19-50417916-G-T

Variant names:

• chr19-50417916-G-T
• rs878854552
• NM_002691.4:c.3293G>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_002691.4(POLD1):​c.3293G>T​(p.Arg1098Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,611,002 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1098C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: POLD1 NM_002691.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 2.51
• Publications: 3 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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.38550478).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002691.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLD1	NM_002691.4	MANE Select	c.3293G>T	p.Arg1098Leu	missense	Exon 27 of 27	NP_002682.2
	POLD1	NM_001308632.1		c.3371G>T	p.Arg1124Leu	missense	Exon 26 of 26	NP_001295561.1
	POLD1	NM_001256849.1		c.3293G>T	p.Arg1098Leu	missense	Exon 27 of 27	NP_001243778.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLD1	ENST00000440232.7	TSL:1 MANE Select	c.3293G>T	p.Arg1098Leu	missense	Exon 27 of 27	ENSP00000406046.1
	POLD1	ENST00000595904.6	TSL:1	c.3371G>T	p.Arg1124Leu	missense	Exon 27 of 27	ENSP00000472445.1
	POLD1	ENST00000599857.7	TSL:1	c.3293G>T	p.Arg1098Leu	missense	Exon 27 of 27	ENSP00000473052.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152094 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1458908 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 725566

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33432

American (AMR) AF: 0.0000225 AC: 1 AN: 44464

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26028

East Asian (EAS) AF: 0.00 AC: 0 AN: 39650

South Asian (SAS) AF: 0.00 AC: 0 AN: 85596

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53016

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110736

Other (OTH) AF: 0.00 AC: 0 AN: 60226

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152094 Hom.: 0 Cov.: 31 AF XY: 0.0000269 AC XY: 2 AN XY: 74272

African (AFR) AF: 0.00 AC: 0 AN: 41408

American (AMR) AF: 0.0000654 AC: 1 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5184

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67990

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000453

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Sep 13, 2017

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

May 12, 2025

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 31034466)

Colorectal cancer, susceptibility to, 10 Uncertain:2

Nov 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 1098 of the POLD1 protein (p.Arg1098Leu). 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: 239341). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on POLD1 protein function. 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.

Aug 17, 2023

St. Jude Molecular Pathology, St. Jude Children's Research Hospital

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The POLD1 c.3293G>T (p.Arg1098Leu) missense change is absent in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL predicts a benign effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant was reported in tumor(s) with <10 mutations/Mb (PMID: 29056344). To our knowledge, this variant has not been reported in the literature in individuals with POLD1-related disease. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance.

Familial colorectal cancer Uncertain:1

Jul 02, 2018

Mendelics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Uncertain:1

Jun 06, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R1098L variant (also known as c.3293G>T), located in coding exon 26 of the POLD1 gene, results from a G to T substitution at nucleotide position 3293. The arginine at codon 1098 is replaced by leucine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.51
BayesDel_addAF	Benign	-0.0045	T
BayesDel_noAF	Benign	-0.24
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.81	D
Eigen	Uncertain	0.35
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Benign	0.53	D
LIST_S2	Benign	0.81	T
M_CAP	Pathogenic	0.38	D
MetaRNN	Benign	0.39	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Pathogenic	4.0	H
PhyloP100		2.5
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-6.7	D
REVEL	Benign	0.21
Sift	Uncertain	0.010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.97	D
Vest4		0.28
MutPred		0.45		Loss of disorder (P = 0.0172)
MVP		0.74
MPC		1.8
ClinPred		0.99	D
GERP RS		2.7
RBP_binding_hub_radar		1.0
RBP_regulation_power_radar		2.1
Varity_R		0.75
gMVP		0.76
Mutation Taster		=31/69	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs878854552; hg19: chr19-50921173;