chr19-50413489-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_002691.4(POLD1):​c.2218A>G​(p.Thr740Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,612,318 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. T740P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

POLD1
NM_002691.4 missense

Scores

1
4
13

Clinical Significance

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

Conservation

PhyloP100: 4.98

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 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

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.2218A>Gp.Thr740Ala
missense
Exon 18 of 27NP_002682.2
POLD1
NM_001308632.1
c.2296A>Gp.Thr766Ala
missense
Exon 17 of 26NP_001295561.1
POLD1
NM_001256849.1
c.2218A>Gp.Thr740Ala
missense
Exon 18 of 27NP_001243778.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
POLD1
ENST00000440232.7
TSL:1 MANE Select
c.2218A>Gp.Thr740Ala
missense
Exon 18 of 27ENSP00000406046.1
POLD1
ENST00000595904.6
TSL:1
c.2296A>Gp.Thr766Ala
missense
Exon 18 of 27ENSP00000472445.1
POLD1
ENST00000599857.7
TSL:1
c.2218A>Gp.Thr740Ala
missense
Exon 18 of 27ENSP00000473052.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152200
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000404
AC:
1
AN:
247442
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000628
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460118
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
726230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33426
American (AMR)
AF:
0.00
AC:
0
AN:
44500
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26114
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39610
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86030
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53210
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111132
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60328
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
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:
0.0000197
AC:
3
AN:
152200
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41454
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:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.0000658
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.00000824
AC:
1

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 17, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 469243). This variant has not been reported in the literature in individuals affected with POLD1-related conditions. This variant is present in population databases (rs781629170, gnomAD 0.007%). This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 740 of the POLD1 protein (p.Thr740Ala). 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. RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (Invitae). Advanced 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 at Invitae 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.

Hereditary cancer-predisposing syndrome Uncertain:1
Nov 16, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.T740A variant (also known as c.2218A>G), located in coding exon 17 of the POLD1 gene, results from an A to G substitution at nucleotide position 2218. The threonine at codon 740 is replaced by alanine, an amino acid with similar 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
Benign
0.090
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.37
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.22
T
Eigen
Benign
0.11
Eigen_PC
Benign
0.17
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.27
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Uncertain
2.7
M
PhyloP100
5.0
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-2.3
N
REVEL
Benign
0.21
Sift
Benign
0.069
T
Sift4G
Benign
0.11
T
Polyphen
0.26
B
Vest4
0.14
MVP
0.60
MPC
1.3
ClinPred
0.53
D
GERP RS
4.3
PromoterAI
0.0091
Neutral
Varity_R
0.33
gMVP
0.67
Mutation Taster
=39/61
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.44
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.44
Position offset: -5

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

Publications

Other links and lift over

dbSNP: rs781629170; hg19: chr19-50916746; API