19-50415477-C-G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_002691.4(POLD1):​c.2604C>G​(p.Ile868Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,460,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. I868V) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

POLD1
NM_002691.4 missense

Scores

7
6
5

Clinical Significance

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

Conservation

PhyloP100: 2.22

Publications

0 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.85

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POLD1NM_002691.4 linkc.2604C>G p.Ile868Met missense_variant Exon 21 of 27 ENST00000440232.7 NP_002682.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POLD1ENST00000440232.7 linkc.2604C>G p.Ile868Met missense_variant Exon 21 of 27 1 NM_002691.4 ENSP00000406046.1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1460872
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
726768
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86236
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52790
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5582
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111888
Other (OTH)
AF:
0.00
AC:
0
AN:
60364
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.515
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
33

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
Jul 11, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 868 of the POLD1 protein (p.Ile868Met). 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: 851572). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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
Feb 20, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I868M variant (also known as c.2604C>G), located in coding exon 20 of the POLD1 gene, results from a C to G substitution at nucleotide position 2604. The isoleucine at codon 868 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. 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
Pathogenic
0.78
BayesDel_addAF
Benign
-0.024
T
BayesDel_noAF
Benign
-0.27
CADD
Uncertain
23
DANN
Uncertain
1.0
DEOGEN2
Benign
0.34
T;.;.;T
Eigen
Uncertain
0.53
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.0
.;.;D;D
M_CAP
Pathogenic
0.57
D
MetaRNN
Pathogenic
0.85
D;D;D;D
MetaSVM
Benign
-0.73
T
MutationAssessor
Pathogenic
4.4
H;.;.;H
PhyloP100
2.2
PrimateAI
Pathogenic
0.89
D
PROVEAN
Uncertain
-3.0
D;.;.;.
REVEL
Uncertain
0.34
Sift
Pathogenic
0.0
D;.;.;.
Sift4G
Pathogenic
0.0
D;D;D;D
Vest4
0.66
ClinPred
1.0
D
GERP RS
3.2
PromoterAI
0.039
Neutral
Varity_R
0.81
gMVP
0.69
Mutation Taster
=24/76
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

Publications

Other links and lift over

dbSNP: rs1060504365; hg19: chr19-50918734; COSMIC: COSV99569991; COSMIC: COSV99569991; API