Genetic Information

Gene & Transcript Details

Gene
POLD1
Transcript
NM_002691.4 MANE Select
Total Exons
Reference Sequence
NC_000019.9
Alternative Transcripts
IDStatusDetails
NM_002691.2 Alternative 3470 nt | 57–3380
NM_002691.4 MANE Select 3436 nt | 46–3369
NM_002691.1 Alternative 3443 nt | 54–3377
NM_002691.3 Alternative 3464 nt | 70–3393

Variant Details

HGVS Notation
NM_002691.4:c.652C>T
Protein Change
R218C
Location
Exon 6 (Exon 6 of )
6
5'Exon Structure3'
Functional Consequence
Loss of Function
Alternate Identifiers

Clinical & Population Data

Population Frequency

gnomAD
Global Frequency
0.0 in 100,000
Extremely Rare
ACMG Criteria Applied PM2
This variant is absent or extremely rare in population databases (PM2 criteria applies).

ClinVar

Open
Classification
Uncertain Significance (VUS)
1 publications
Clinical Statement

"This variant has been reported in ClinVar as Uncertain significance (5 clinical laboratories)."

COSMIC Somatic Evidence

Open
COSMIC ID
COSM6977833
Recurrence
1 occurrences
PM1 Criteria
Not Applied
COSMIC Database Preview
COSMIC Preview
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Functional Impact & Domains

Functional Domain

Hotspot Status
Not a hotspot
Domain Summary
This variant is not located in a mutational hotspot or critical domain.
Related Variants in This Domain
No evidence of other pathogenic variants at this position in gene POLD1.

Functional Studies & Therapeutic Relevance

Functional Summary

The POLD1 R218C variant has not been functionally characterized.

Database Previews
OncoKB
OncoKB Preview
JAX-CKB
JAX-CKB Preview

Click on previews to view full database entries. External databases may require institutional access.

Computational Analysis

Pathogenicity Predictions

SpliceAI
Predictor Consensus
Mixed/VUS
PP3 Applied
No
REVEL Score
0.311
Threshold: ≥0.75 = PP3 applied

SpliceAI Scores

Window: ±500bp
Effect Type Score Position
- Acceptor Loss (AL) 0.0 -351 bp
- Donor Loss (DL) 0.0 106 bp
+ Acceptor Gain (AG) 0.01 36 bp
+ Donor Gain (DG) 0.0 268 bp
High impact (≥0.5) Medium impact (0.2-0.49) Low impact (<0.2)

VCEP Guidelines

Applied ACMG/AMP Criteria (VCEP Specific)

Filter Criteria:
PVS1

PVS1 (Not Applied)

According to standard ACMG guidelines, the rule for PVS1 is: "Null variant (nonsense, frameshift, canonical ±1 or 2 splice sites, initiation codon, single exon or multiexon deletion) in a gene where loss of function is a known mechanism of disease." The evidence for this variant shows it is a missense change (R218C), not a null variant. Therefore, this criterion is not applied.

PS1

PS1 (Not Applied)

According to standard ACMG guidelines, the rule for PS1 is: "Same amino acid change as a known pathogenic variant but different nucleotide change." The evidence for this variant shows no previously established pathogenic variant at codon 218. Therefore, this criterion is not applied.

PS2

PS2 (Not Applied)

According to standard ACMG guidelines, the rule for PS2 is: "De novo (both maternity and paternity confirmed) in a patient with the disease and no family history." No de novo data are available for this variant. Therefore, this criterion is not applied.

PS3

PS3 (Not Applied)

According to standard ACMG guidelines, the rule for PS3 is: "Well-established functional studies supportive of a damaging effect on the gene or gene product." No functional studies have been performed for POLD1 R218C. Therefore, this criterion is not applied.

PS4

PS4 (Not Applied)

According to standard ACMG guidelines, the rule for PS4 is: "Prevalence in affected individuals is significantly increased compared with controls." There are no case-control or affected-individual data for this variant. Therefore, this criterion is not applied.

PM1

PM1 (Not Applied)

According to standard ACMG guidelines, the rule for PM1 is: "Located in a mutational hotspot and/or well-established functional domain without benign variation." There is no evidence that residue R218 lies in a defined mutational hotspot or domain of known increased pathogenic variant density. Therefore, this criterion is not applied.

PM2

PM2 (Moderate)

According to standard ACMG guidelines, the rule for PM2 is: "Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium." The evidence for this variant shows it is absent from gnomAD (MAF=0%). Therefore, this criterion is applied at Moderate strength because the variant is not found in population databases.

PM3

PM3 (Not Applied)

According to standard ACMG guidelines, the rule for PM3 is: "Detected in trans with a pathogenic variant for a recessive disorder." There is no information on trans configuration with another POLD1 variant. Therefore, this criterion is not applied.

PM4

PM4 (Not Applied)

According to standard ACMG guidelines, the rule for PM4 is: "Protein length changes due to in-frame deletions/insertions or stop-loss variants." This variant is a single amino acid substitution, not an in-frame indel or stop-loss. Therefore, this criterion is not applied.

PM5

PM5 (Not Applied)

According to standard ACMG guidelines, the rule for PM5 is: "Novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen." There are no known pathogenic missense changes reported at residue R218. Therefore, this criterion is not applied.

PM6

PM6 (Not Applied)

According to standard ACMG guidelines, the rule for PM6 is: "Assumed de novo, but without confirmation of paternity and maternity." No de novo or parental data exist. Therefore, this criterion is not applied.

PP1

PP1 (Not Applied)

According to standard ACMG guidelines, the rule for PP1 is: "Co-segregation with disease in multiple affected family members in a gene definitively known to cause the disease." No segregation data are available. Therefore, this criterion is not applied.

PP2

PP2 (Not Applied)

According to standard ACMG guidelines, the rule for PP2 is: "Missense variant in a gene with low rate of benign missense variation where missense is a common mechanism of disease." While POLD1 missense variants can cause disease, there is insufficient evidence on the rate of benign missense variation. Therefore, this criterion is not applied.

PP3

PP3 (Not Applied)

According to standard ACMG guidelines, the rule for PP3 is: "Multiple lines of computational evidence support a deleterious effect on the gene or gene product." Computational predictions for R218C are mixed, with the majority indicating benign impact. Therefore, this criterion is not applied.

PP4

PP4 (Not Applied)

According to standard ACMG guidelines, the rule for PP4 is: "Patient's phenotype or family history is highly specific for a disease with a single genetic etiology." No phenotype or family history data specific to POLD1-related disease are provided. Therefore, this criterion is not applied.

PP5

PP5 (Not Applied)

According to standard ACMG guidelines, the rule for PP5 is: "Reputable source reports variant as pathogenic, but without accessible evidence." ClinVar reports this variant as VUS, not pathogenic. Therefore, this criterion is not applied.

BA1

BA1 (Not Applied)

According to standard ACMG guidelines, the rule for BA1 is: "Allele frequency is >5% in controls." The variant frequency is 0%. Therefore, this criterion is not applied.

BS1

BS1 (Not Applied)

According to standard ACMG guidelines, the rule for BS1 is: "Allele frequency is greater than expected for disorder." The variant is absent from population databases. Therefore, this criterion is not applied.

BS2

BS2 (Not Applied)

According to standard ACMG guidelines, the rule for BS2 is: "Observed in a healthy adult individual for a dominant disorder with full penetrance expected at an early age." No such observations are reported. Therefore, this criterion is not applied.

BS3

BS3 (Not Applied)

According to standard ACMG guidelines, the rule for BS3 is: "Well-established functional studies show no damaging effect on protein function or splicing." No functional studies are available. Therefore, this criterion is not applied.

BS4

BS4 (Not Applied)

According to standard ACMG guidelines, the rule for BS4 is: "Lack of segregation in affected family members." No segregation analysis is available. Therefore, this criterion is not applied.

BP1

BP1 (Not Applied)

According to standard ACMG guidelines, the rule for BP1 is: "Missense variant in a gene where only loss of function causes disease." POLD1 disease is associated with specific missense changes, not exclusively LoF. Therefore, this criterion is not applied.

BP2

BP2 (Not Applied)

According to standard ACMG guidelines, the rule for BP2 is: "Observed in trans with a pathogenic variant for dominant disorders or in cis with a pathogenic variant." No data on co-occurrence with other variants are available. Therefore, this criterion is not applied.

BP3

BP3 (Not Applied)

According to standard ACMG guidelines, the rule for BP3 is: "In-frame deletions/insertions in a repetitive region without known function." This variant is a missense substitution. Therefore, this criterion is not applied.

BP4

BP4 (Supporting)

According to standard ACMG guidelines, the rule for BP4 is: "Multiple lines of computational evidence suggest no impact on gene or gene product (conservation, evolutionary, splicing impact, etc.)." Computational tools (CADD, MetaSVM, MetaLR, PrimateAI, REVEL=0.31) and SpliceAI (score=0.01) predict benign or no impact. Therefore, this criterion is applied at Supporting strength because the consensus is no deleterious effect.

BP5

BP5 (Not Applied)

According to standard ACMG guidelines, the rule for BP5 is: "Variant found in a case with an alternate molecular basis for disease." No such alternate molecular basis is reported. Therefore, this criterion is not applied.

BP6

BP6 (Not Applied)

According to standard ACMG guidelines, the rule for BP6 is: "Reputable source reports variant as benign, but without accessible evidence." This variant is reported in ClinVar as VUS, not benign. Therefore, this criterion is not applied.

BP7

BP7 (Not Applied)

According to standard ACMG guidelines, the rule for BP7 is: "Synonymous variant with no predicted impact on splicing." This is a missense variant. Therefore, this criterion is not applied.