NM_002691.4:c.1937T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_002691.4(POLD1):​c.1937T>C​(p.Phe646Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,613,692 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. F646Y) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

POLD1
NM_002691.4 missense

Scores

9
9

Clinical Significance

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

Conservation

PhyloP100: 5.40

Publications

1 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: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.977

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
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
POLD1
NM_002691.4
MANE Select
c.1937T>Cp.Phe646Ser
missense
Exon 16 of 27NP_002682.2
POLD1
NM_001308632.1
c.2015T>Cp.Phe672Ser
missense
Exon 15 of 26NP_001295561.1
POLD1
NM_001256849.1
c.1937T>Cp.Phe646Ser
missense
Exon 16 of 27NP_001243778.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
POLD1
ENST00000440232.7
TSL:1 MANE Select
c.1937T>Cp.Phe646Ser
missense
Exon 16 of 27ENSP00000406046.1
POLD1
ENST00000595904.6
TSL:1
c.2015T>Cp.Phe672Ser
missense
Exon 16 of 27ENSP00000472445.1
POLD1
ENST00000599857.7
TSL:1
c.1937T>Cp.Phe646Ser
missense
Exon 16 of 27ENSP00000473052.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152176
Hom.:
0
Cov.:
32
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
AF:
0.00000274
AC:
4
AN:
1461516
Hom.:
0
Cov.:
31
AF XY:
0.00000275
AC XY:
2
AN XY:
727092
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39696
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53248
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111844
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
0
1
1
2
2
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
AF:
0.00000657
AC:
1
AN:
152176
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74354
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000132
Hom.:
0

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
Sep 15, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces phenylalanine with serine at codon 646 of the POLD1 protein (p.Phe646Ser). The phenylalanine residue is highly conserved and there is a large physicochemical difference between phenylalanine and serine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with POLD1-related conditions. 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
Jan 21, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.F646S variant (also known as c.1937T>C), located in coding exon 15 of the POLD1 gene, results from a T to C substitution at nucleotide position 1937. The phenylalanine at codon 646 is replaced by serine, an amino acid with highly dissimilar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.27
D
BayesDel_noAF
Pathogenic
0.16
CADD
Pathogenic
30
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.49
T
Eigen
Pathogenic
0.95
Eigen_PC
Pathogenic
0.79
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.96
D
M_CAP
Uncertain
0.24
D
MetaRNN
Pathogenic
0.98
D
MetaSVM
Uncertain
0.031
D
MutationAssessor
Pathogenic
5.3
H
PhyloP100
5.4
PrimateAI
Uncertain
0.79
T
PROVEAN
Pathogenic
-8.0
D
REVEL
Uncertain
0.63
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.0040
D
Polyphen
1.0
D
Vest4
0.97
MutPred
0.87
Gain of disorder (P = 0.0089)
MVP
0.74
MPC
2.1
ClinPred
1.0
D
GERP RS
4.5
Varity_R
0.98
gMVP
0.95
Mutation Taster
=10/90
disease causing

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

Other links and lift over

dbSNP: rs767518281; hg19: chr19-50912423; API