chr19-50398910-G-C

Position:

• chr19-50398910-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_002691.4(POLD1):​c.59G>C​(p.Gly20Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000691 in 1,446,674 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: POLD1 NM_002691.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 0.385

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11626461).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLD1	NM_002691.4	c.59G>C	p.Gly20Ala	missense_variant	2/27	ENST00000440232.7	NP_002682.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7	c.59G>C	p.Gly20Ala	missense_variant	2/27	1	NM_002691.4	ENSP00000406046.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.91e-7 AC: 1 AN: 1446674 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 718192

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000167

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Aug 03, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Colorectal cancer, susceptibility to, 10 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 03, 2023

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. 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: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 654641). This variant has not been reported in the literature in individuals affected with POLD1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 20 of the POLD1 protein (p.Gly20Ala). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 06, 2022

The p.G20A variant (also known as c.59G>C), located in coding exon 1 of the POLD1 gene, results from a G to C substitution at nucleotide position 59. The glycine at codon 20 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 v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Benign	-0.30	T
BayesDel_noAF	Benign	-0.67
CADD	Benign	3.4
DANN	Benign	0.62
DEOGEN2	Benign	0.16	T;.;.;.;T;.
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.54	D
LIST_S2	Benign	0.62	.;.;T;T;T;T
M_CAP	Benign	0.0082	T
MetaRNN	Benign	0.12	T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.55	N;.;.;.;N;.
PrimateAI	Uncertain	0.60	T
PROVEAN	Benign	-0.47	N;.;.;.;.;.
REVEL	Benign	0.011
Sift	Benign	0.23	T;.;.;.;.;.
Sift4G	Benign	0.41	T;T;D;T;T;D
Polyphen		0.0	B;.;.;.;B;.
Vest4		0.17
MutPred		0.23		Loss of relative solvent accessibility (P = 0.0306);Loss of relative solvent accessibility (P = 0.0306);Loss of relative solvent accessibility (P = 0.0306);Loss of relative solvent accessibility (P = 0.0306);Loss of relative solvent accessibility (P = 0.0306);Loss of relative solvent accessibility (P = 0.0306);
MVP		0.16
MPC		0.20
ClinPred		0.015	T
GERP RS		-0.49
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.026
gMVP		0.24

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

Other links and lift over

dbSNP: rs778329225; hg19: chr19-50902167;