rs1555792888

Positions:

• chr19-50414968-C-A
• chr19-50414968-C-G
• chr19-50414968-C-T

Variant summary

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

The ENST00000440232.7(POLD1):​c.2542C>A​(p.Leu848Met) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. L848V) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: POLD1 ENST00000440232.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.65

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, 0.919

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLD1	NM_002691.4	c.2542C>A	p.Leu848Met	missense_variant	20/27	ENST00000440232.7	NP_002682.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLD1	ENST00000440232.7	c.2542C>A	p.Leu848Met	missense_variant	20/27	1	NM_002691.4	ENSP00000406046	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

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

Sep 25, 2019

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: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with POLD1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with methionine at codon 848 of the POLD1 protein (p.Leu848Met). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and methionine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Benign	-0.025	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.38	T;.;.;T
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Benign	0.73	D
LIST_S2	Benign	0.79	.;.;T;T
M_CAP	Pathogenic	0.61	D
MetaRNN	Pathogenic	0.92	D;D;D;D
MetaSVM	Benign	-0.60	T
MutationAssessor	Pathogenic	4.2	H;.;.;H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.86	D
PROVEAN	Benign	-2.0	N;.;.;.
REVEL	Uncertain	0.35
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	D;.;.;D
Vest4		0.62
MutPred		0.84		Gain of MoRF binding (P = 0.2679);.;.;Gain of MoRF binding (P = 0.2679);
MVP		0.62
MPC		1.6
ClinPred		1.0	D
GERP RS		2.5
Varity_R		0.65
gMVP		0.64

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: rs1555792888; hg19: chr19-50918225;