Genetic Variant NM_002691.4:c.623C>T (chr19-50402238-C-T) – ACMG Classification: Likely_benign (-5 pts)

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4BS2

The NM_002691.4(POLD1):c.623C>T(p.Pro208Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000153 in 1,440,252 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 (★★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

POLD1
NM_002691.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1O:1

Conservation

PhyloP100: 1.30

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.37366283).

BS2

High AC in GnomAdExome4 at 22 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLD1	NM_002691.4 link	c.623C>T	p.Pro208Leu	missense_variant	Exon 6 of 27	ENST00000440232.7	NP_002682.2	P28340A0A024R4F4Q59FA0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7 link	c.623C>T	p.Pro208Leu	missense_variant	Exon 6 of 27	1	NM_002691.4	ENSP00000406046.1		P28340

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000429

AC:

AN:

232954

Hom.:

AF XY:

0.00000796

AC XY:

AN XY:

125616

show subpopulations

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000950

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000153

AC:

AN:

1440252

Hom.:

Cov.:

AF XY:

0.0000182

AC XY:

AN XY:

714114

show subpopulations

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:

0.0000484

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000154

Gnomad4 OTH exome

AF:

0.0000168

GnomAD4 genome

Cov.:

ExAC

AF:

0.00000825

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Colorectal cancer, susceptibility to, 10

Uncertain:2

May 04, 2022

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.623C>T (p.Pro208Leu) missense change has a maximum subpopulation frequency of 0.00095% in gnomAD v2.1.1 (PM2_supporting; https://gnomad.broadinstitute.org/). It is predicted to have a benign effect on protein function (BP4), but to our knowledge this prediction has not been confirmed by functional studies. This variant has been reported in four tumors with a high tumor mutational burden and one tumor with a low tumor mutational burden (PMID: 29056344). To our knowledge, this variant has not been reported in the literature in individuals with POLD1-related disease. In summary, this variant meets criteria to be classified as of uncertain significance based on the ACMG/AMP criteria: PM2_supporting, BP4. -

Feb 02, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 208 of the POLD1 protein (p.Pro208Leu). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. 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: 537100). 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) indicates that this missense variant is not expected to disrupt POLD1 protein function with a negative predictive value of 80%. 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. -

not specified

Uncertain:1

Mar 04, 2025

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Uncertain:1

Nov 22, 2024

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: 29056344) -

Hereditary cancer-predisposing syndrome

Benign:1

Dec 19, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Colorectal cancer, susceptibility to, 10;C3715192:Mandibular hypoplasia-deafness-progeroid syndrome

Other:1

GenomeConnect - Invitae Patient Insights Network

Significance: not provided

Review Status: no classification provided

Collection Method: phenotyping only

Variant interpreted as Uncertain significance and reported on 12-18-2017 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.076

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.46

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.43

T;.;.;T

Eigen

Benign

-0.42

Eigen_PC

Benign

-0.35

FATHMM_MKL

Benign

0.33

LIST_S2

Benign

0.84

.;.;T;T

M_CAP

Benign

0.016

MetaRNN

Benign

0.37

T;T;T;T

MetaSVM

Benign

-1.0

MutationAssessor

Uncertain

2.1

M;.;.;M

PrimateAI

Uncertain

0.57

PROVEAN

Pathogenic

-4.9

D;.;.;.

REVEL

Benign

0.10

Sift

Benign

0.13

T;.;.;.

Sift4G

Benign

0.57

T;T;T;T

Polyphen

0.0060

B;.;.;B

Vest4

0.34

MutPred

0.59

Gain of catalytic residue at P208 (P = 0.0423);Gain of catalytic residue at P208 (P = 0.0423);Gain of catalytic residue at P208 (P = 0.0423);Gain of catalytic residue at P208 (P = 0.0423);

MVP

0.56

MPC

0.20

ClinPred

0.47

GERP RS

4.2

RBP_binding_hub_radar

0.97

RBP_regulation_power_radar

2.8

Varity_R

0.11

gMVP

0.52

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over