19-50399053-G-T

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_002691.4(POLD1):c.202G>T(p.Gly68Trp) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,232 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. 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. G68E) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

POLD1
NM_002691.4 missense, splice_region

Scores

Splicing: ADA: 0.9996

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.27

Publications

3 publications found

Variant links:

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

POLD1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLD1	NM_002691.4 link	c.202G>T	p.Gly68Trp	missense_variant, splice_region_variant	Exon 2 of 27	ENST00000440232.7	NP_002682.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7 link	c.202G>T	p.Gly68Trp	missense_variant, splice_region_variant	Exon 2 of 27	1	NM_002691.4	ENSP00000406046.1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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

Data not reliable, filtered out with message: AC0

AF:

0.00

AC:

AN:

1399572

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

690380

African (AFR)

AF:

0.00

AC:

AN:

31692

American (AMR)

AF:

0.00

AC:

AN:

35762

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25184

East Asian (EAS)

AF:

0.00

AC:

AN:

35944

South Asian (SAS)

AF:

0.00

AC:

AN:

79226

European-Finnish (FIN)

AF:

0.00

AC:

AN:

49486

Middle Eastern (MID)

AF:

0.00

AC:

AN:

4678

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1079582

Other (OTH)

AF:

0.00

AC:

AN:

58018

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74384

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41460

American (AMR)

AF:

0.00

AC:

AN:

15286

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5200

South Asian (SAS)

AF:

0.00

AC:

AN:

4834

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10622

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68040

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.475

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Colorectal cancer, susceptibility to, 10

Uncertain:1

Oct 10, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with tryptophan, which is neutral and slightly polar, at codon 68 of the POLD1 protein (p.Gly68Trp). This variant also falls at the last nucleotide of exon 2, which is part of the consensus splice site for this exon. 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: 841066). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant¬†is likely to be tolerated. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this missense change is associated with inconclusive levels of altered splicing (internal data). 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

Sep 11, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.G68W variant (also known as c.202G>T), located in coding exon 1 of the POLD1 gene, results from a G to T substitution at nucleotide position 202. The glycine at codon 68 is replaced by tryptophan, an amino acid with highly dissimilar properties. However, this change occurs in the last base pair of coding exon 1, which makes it likely to have some effect on normal mRNA splicing. This nucleotide position is highly conserved in available vertebrate species. This amino acid position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. In addition, as a missense substitution this is predicted to be tolerated by in silico analysis. However, loss of function 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

AlphaMissense

Benign

0.14

BayesDel_addAF

Benign

-0.044

BayesDel_noAF

Benign

-0.30

CADD

Pathogenic

(source)

DANN

Uncertain

0.99

DEOGEN2

Benign

0.39

T;.;.;.;T;.

Eigen

Benign

0.093

Eigen_PC

Benign

-0.11

FATHMM_MKL

Uncertain

0.91

LIST_S2

Benign

0.0

.;.;T;T;T;T

M_CAP

Benign

0.020

MetaRNN

Benign

0.26

T;T;T;T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.55

N;.;.;.;N;.

PhyloP100

2.3

PrimateAI

Uncertain

0.53

PROVEAN

Benign

-2.1

N;.;.;.;.;.

REVEL

Benign

0.14

Sift

Uncertain

0.018

D;.;.;.;.;.

Sift4G

Uncertain

0.016

D;D;D;D;D;D

Vest4

0.57

ClinPred

0.65

GERP RS

2.3

PromoterAI

-0.095

Neutral

(source)

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.8

Varity_R

0.060

gMVP

0.47

Mutation Taster

=43/57

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.97

SpliceAI score (max)

0.63

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.63

Position offset: 0

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over