19-50406240-C-T

Position:

• chr19-50406240-C-T

Variant summary

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

The NM_002691.4(POLD1):​c.1301C>T​(p.Ser434Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,812 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 (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: POLD1 NM_002691.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.55

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLD1	NM_002691.4	c.1301C>T	p.Ser434Phe	missense_variant	11/27	ENST00000440232.7	NP_002682.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7	c.1301C>T	p.Ser434Phe	missense_variant	11/27	1	NM_002691.4	ENSP00000406046.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461812 Hom.: 0 Cov.: 36 AF XY: 0.00000138 AC XY: 1 AN XY: 727218

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: 0.0000187

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Colorectal cancer, susceptibility to, 10 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 13, 2022

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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 1006251). 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 serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 434 of the POLD1 protein (p.Ser434Phe). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 18, 2023

The p.S434F variant (also known as c.1301C>T), located in coding exon 10 of the POLD1 gene, results from a C to T substitution at nucleotide position 1301. The serine at codon 434 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This amino acid position is well conserved in available vertebrate species. 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	0.26
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.42
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Benign	0.39	T;.;.;T
Eigen	Uncertain	0.34
Eigen_PC	Uncertain	0.30
FATHMM_MKL	Uncertain	0.80	D
LIST_S2	Uncertain	0.97	.;.;D;D
M_CAP	Benign	0.039	D
MetaRNN	Benign	0.42	T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Uncertain	2.7	M;.;.;M
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-3.4	D;.;.;.
REVEL	Benign	0.11
Sift	Uncertain	0.0030	D;.;.;.
Sift4G	Uncertain	0.0090	D;D;D;D
Polyphen		0.74	P;.;.;P
Vest4		0.48
MutPred		0.48		Loss of disorder (P = 0.005);Loss of disorder (P = 0.005);Loss of disorder (P = 0.005);Loss of disorder (P = 0.005);
MVP		0.61
MPC		1.5
ClinPred		0.97	D
GERP RS		3.5
Varity_R		0.74
gMVP		0.63

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.34		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.34		Position offset: 11

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060501845; hg19: chr19-50909497;