NM_002691.4:c.947A>G

Variant names:

• chr19-50402718-A-G
• rs1555790301
• NM_002691.4:c.947A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_002691.4(POLD1):​c.947A>G​(p.Asp316Gly) variant causes a missense change involving the alteration of a conserved nucleotide. 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. D316N) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: POLD1 NM_002691.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.27
• Publications: 4 publications found

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 Gene-Disease associations (from GenCC):

• POLD1-related polyposis and colorectal cancer syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• colorectal cancer, susceptibility to, 10

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
• mandibular hypoplasia-deafness-progeroid syndrome

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Genomics England PanelApp, Ambry Genetics, Orphanet, G2P
• Polymerase proofreading-related adenomatous polyposis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• immunodeficiency 120

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
• non-severe combined immunodeficiency due to polymerase delta deficiency

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002691.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLD1	NM_002691.4	MANE Select	c.947A>G	p.Asp316Gly	missense	Exon 8 of 27	NP_002682.2
	POLD1	NM_001308632.1		c.947A>G	p.Asp316Gly	missense	Exon 7 of 26	NP_001295561.1
	POLD1	NM_001256849.1		c.947A>G	p.Asp316Gly	missense	Exon 8 of 27	NP_001243778.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLD1	ENST00000440232.7	TSL:1 MANE Select	c.947A>G	p.Asp316Gly	missense	Exon 8 of 27	ENSP00000406046.1
	POLD1	ENST00000595904.6	TSL:1	c.947A>G	p.Asp316Gly	missense	Exon 8 of 27	ENSP00000472445.1
	POLD1	ENST00000599857.7	TSL:1	c.947A>G	p.Asp316Gly	missense	Exon 8 of 27	ENSP00000473052.1

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

Hereditary cancer-predisposing syndrome Uncertain:1

Mar 25, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D316G variant (also known as c.947A>G), located in coding exon 7 of the POLD1 gene, results from an A to G substitution at nucleotide position 947. The aspartic acid at codon 316 is replaced by glycine, an amino acid with similar properties. This alteration has been identified in a Lynch syndrome-like family and considered pathogenic by authors (Bellido F et al, Genet. Med. 2016 Apr; 18(4):325-32). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.55
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.39	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.27	D
MutationAssessor	Pathogenic	3.7	H
PhyloP100		8.3
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-6.9	D
REVEL	Pathogenic	0.77
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.91		Loss of stability (P = 0.0661)
MVP		0.87
MPC		0.86
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.98
gMVP		0.93
Mutation Taster		=4/96	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1555790301; hg19: chr19-50905975; COSMIC: COSV101486824; COSMIC: COSV101486824;