19-50402741-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_002691.4(POLD1):c.970G>C(p.Gly324Arg) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. 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. G324D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: POLD1 NM_002691.4 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.09

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POLD1	NM_002691.4	c.970G>C	p.Gly324Arg	missense_variant, splice_region_variant	8/27	ENST00000440232.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLD1	ENST00000440232.7	c.970G>C	p.Gly324Arg	missense_variant, splice_region_variant	8/27	1	NM_002691.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

POLD1-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Dec 05, 2019

The POLD1 c.970G>C (p.Gly324Arg) variant is a missense variant. A literature search was performed for the gene, cDNA change, and amino acid change. No publications were found based on this search. The p.Gly324Arg variant is not found in the Genome Aggregation Database, in a region of good sequence coverage, so is presumed to be rare. The Gly324 residue maps to the exonuclease domain of the protein. Based on the limited evidence, the p.Gly324Arg variant is classified as a variant of unknown significance for POLD1-related disorders. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
Cadd	Pathogenic	34
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.51	D;.;.;D
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.90	D;D;D;D
MetaSVM	Benign	-0.68	T
MutationAssessor	Pathogenic	3.7	H;.;.;H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-7.8	D;.;.;.
REVEL	Uncertain	0.49
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;.;.;D
Vest4		0.47
MutPred		0.86		Gain of solvent accessibility (P = 0.019);Gain of solvent accessibility (P = 0.019);Gain of solvent accessibility (P = 0.019);Gain of solvent accessibility (P = 0.019);
MVP		0.74
MPC		0.82
ClinPred		1.0	D
GERP RS		4.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.80

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.77		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.77		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1160832458; hg19: chr19-50905998;