Genetic Variant POLB:p.Ala23Ser (chr8-42339017-G-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

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

The NM_002690.3(POLB):c.67G>T(p.Ala23Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000192 in 1,461,298 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

POLB
NM_002690.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.23

Variant links:

Genes affected

POLB (HGNC:9174): (DNA polymerase beta) The protein encoded by this gene is a DNA polymerase involved in base excision and repair, also called gap-filling DNA synthesis. The encoded protein, acting as a monomer, is normally found in the cytoplasm, but it translocates to the nucleus upon DNA damage. Several transcript variants of this gene exist, but the full-length nature of only one has been described to date. [provided by RefSeq, Sep 2011]

POLB links:

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ACMG classification

Classification made for transcript

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 rank	MANE	Protein	UniProt
POLB	NM_002690.3 link	c.67G>T	p.Ala23Ser	missense_variant	Exon 2 of 14	ENST00000265421.9	NP_002681.1	P06746

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLB	ENST00000265421.9 link	c.67G>T	p.Ala23Ser	missense_variant	Exon 2 of 14	1	NM_002690.3	ENSP00000265421.4		P06746

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251474

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000192

AC:

AN:

1461298

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727020

show subpopulations

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:

0.0000225

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000312

Hom.:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

May 26, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.67G>T (p.A23S) alteration is located in exon 2 (coding exon 2) of the POLB gene. This alteration results from a G to T substitution at nucleotide position 67, causing the alanine (A) at amino acid position 23 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.34

BayesDel_addAF

Uncertain

0.014

BayesDel_noAF

Benign

-0.22

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.49

T;T

Eigen

Pathogenic

0.72

Eigen_PC

Pathogenic

0.70

FATHMM_MKL

Uncertain

0.92

LIST_S2

Uncertain

0.95

D;D

M_CAP

Benign

0.052

MetaRNN

Uncertain

0.54

D;D

MetaSVM

Benign

-0.50

MutationAssessor

Uncertain

2.3

M;.

PrimateAI

Uncertain

0.72

PROVEAN

Benign

-2.0

N;N

REVEL

Benign

0.15

Sift

Benign

0.091

T;T

Sift4G

Uncertain

0.028

D;D

Polyphen

0.94

P;.

Vest4

0.55

MutPred

0.57

Gain of disorder (P = 0.0637);Gain of disorder (P = 0.0637);

MVP

0.63

MPC

1.4

ClinPred

0.93

GERP RS

5.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.58

gMVP

0.66

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over