X-24693969-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_ModerateBS1_Supporting

The NM_001330360.2(POLA1):c.8C>T(p.Pro3Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000276 in 1,194,244 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 9 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000018 ( 0 hom., 0 hem., cov: 25)

Exomes 𝑓: 0.000029 ( 0 hom. 9 hem. )

Consequence

POLA1
NM_001330360.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.200

Variant links:

Genes affected

POLA1 (HGNC:9173): (DNA polymerase alpha 1, catalytic subunit) This gene encodes the catalytic subunit of DNA polymerase, which together with a regulatory and two primase subunits, forms the DNA polymerase alpha complex. The catalytic subunit plays an essential role in the initiation of DNA replication. [provided by RefSeq, Mar 2010]

POLA1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.06868413).

BS1

Variant frequency is greater than expected in population nfe. gnomad4_exome allele frequency = 0.0000287 (31/1080888) while in subpopulation NFE AF= 0.0000372 (31/833306). AF 95% confidence interval is 0.0000266. There are 0 homozygotes in gnomad4_exome. There are 9 alleles in male gnomad4_exome subpopulation. Median coverage is 29. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POLA1	NM_001330360.2 linkuse as main transcript	c.8C>T	p.Pro3Leu	missense_variant	1/37	ENST00000379068.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLA1	ENST00000379068.8 linkuse as main transcript	c.8C>T	p.Pro3Leu	missense_variant	1/37	5	NM_001330360.2	A1

Frequencies

GnomAD3 genomes

AF:

0.0000176

AC:

AN:

113356

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

35488

show subpopulations

Gnomad AFR

AF:

0.0000319

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000187

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000202

AC:

AN:

148601

Hom.:

AF XY:

0.0000220

AC XY:

AN XY:

45495

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:

0.0000475

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000287

AC:

AN:

1080888

Hom.:

Cov.:

AF XY:

0.0000256

AC XY:

AN XY:

352004

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:

0.0000372

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000176

AC:

AN:

113356

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

35488

show subpopulations

Gnomad4 AFR

AF:

0.0000319

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000187

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ExAC

AF:

0.0000168

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 18, 2023

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 3 of the POLA1 protein (p.Pro3Leu). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with POLA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1941822). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.38

BayesDel_addAF

Benign

-0.42

BayesDel_noAF

Benign

-0.84

Cadd

Benign

Dann

Benign

0.93

FATHMM_MKL

Benign

0.0076

LIST_S2

Benign

0.71

T;T;T

M_CAP

Benign

0.0036

MetaRNN

Benign

0.069

T;T;T

MetaSVM

Benign

-1.0

MutationTaster

Benign

1.0

N;N

PrimateAI

Uncertain

0.50

PROVEAN

Benign

-1.8

N;.;N

REVEL

Benign

0.024

Sift

Benign

0.064

T;.;T

Sift4G

Uncertain

0.016

D;D;D

Polyphen

0.0

B;.;B

Vest4

0.12

MVP

0.082

MPC

0.34

ClinPred

0.037

GERP RS

1.7

Varity_R

0.047

gMVP

0.42

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.11

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