chr19-50401832-T-G

Position:

• chr19-50401832-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_002691.4(POLD1):​c.371T>G​(p.Val124Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,598 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. V124A) has been classified as Likely benign.

• 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, single submitter U:1
• Conservation: PhyloP100: 5.35

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.933

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POLD1	NM_002691.4	c.371T>G	p.Val124Gly	missense_variant	4/27	ENST00000440232.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLD1	ENST00000440232.7	c.371T>G	p.Val124Gly	missense_variant	4/27	1	NM_002691.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461598 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 727128

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Colorectal cancer, susceptibility to, 10 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 31, 2018

This variant has not been reported in the literature in individuals with POLD1-related disease. 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: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency). This sequence change replaces valine with glycine at codon 124 of the POLD1 protein (p.Val124Gly). The valine residue is weakly conserved and there is a moderate physicochemical difference between valine and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.60
BayesDel_addAF	Uncertain	0.023	T
BayesDel_noAF	Benign	-0.20
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.81	D;.;.;.;D
Eigen	Benign	0.0052
Eigen_PC	Benign	-0.055
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.76	.;.;T;D;D
M_CAP	Benign	0.032	D
MetaRNN	Pathogenic	0.93	D;D;D;D;D
MetaSVM	Benign	-1.1	T
MutationAssessor	Uncertain	2.7	M;.;.;.;M
MutationTaster	Benign	0.91	D
PrimateAI	Benign	0.40	T
PROVEAN	Pathogenic	-6.6	D;.;.;.;.
REVEL	Uncertain	0.38
Sift	Uncertain	0.0070	D;.;.;.;.
Sift4G	Uncertain	0.0060	D;D;D;D;D
Polyphen		0.55	P;.;.;.;P
Vest4		0.45
MutPred		0.83		Gain of disorder (P = 0.0138);Gain of disorder (P = 0.0138);Gain of disorder (P = 0.0138);Gain of disorder (P = 0.0138);Gain of disorder (P = 0.0138);
MVP		0.63
MPC		0.65
ClinPred		0.95	D
GERP RS		4.0
Varity_R		0.93
gMVP		0.84

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: rs199993010; hg19: chr19-50905089;