15-89318729-A-G

Variant names:

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_StrongBP6_StrongBP7

The NM_002693.3(POLG):c.3294T>C(p.Asn1098Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000706 in 1,613,936 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★★).

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000067 ( 0 hom. )

Consequence

POLG
NM_002693.3 synonymous

Scores

Clinical Significance

Uncertain significance reviewed by expert panel U:1B:5

Conservation

PhyloP100: 1.78

Variant links:

Genes affected

POLG (HGNC:9179): (DNA polymerase gamma, catalytic subunit) Mitochondrial DNA polymerase is heterotrimeric, consisting of a homodimer of accessory subunits plus a catalytic subunit. The protein encoded by this gene is the catalytic subunit of mitochondrial DNA polymerase. The encoded protein contains a polyglutamine tract near its N-terminus that may be polymorphic. Defects in this gene are a cause of progressive external ophthalmoplegia with mitochondrial DNA deletions 1 (PEOA1), sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO), Alpers-Huttenlocher syndrome (AHS), and mitochondrial neurogastrointestinal encephalopathy syndrome (MNGIE). Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2008]

POLG links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -9 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.62).

BP6

Variant 15-89318729-A-G is Benign according to our data. Variant chr15-89318729-A-G is described in ClinVar as [Uncertain_significance]. Clinvar id is 138759.Status of the report is reviewed_by_expert_panel, 3 stars. We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Benign=1, Uncertain_significance=1}.

BP7

Synonymous conserved (PhyloP=1.78 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLG	NM_002693.3 link	c.3294T>C	p.Asn1098Asn	synonymous_variant	Exon 21 of 23	ENST00000268124.11	NP_002684.1	P54098E5KNU5
POLG	NM_001126131.2 link	c.3294T>C	p.Asn1098Asn	synonymous_variant	Exon 21 of 23		NP_001119603.1	P54098E5KNU5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLG	ENST00000268124.11 link	c.3294T>C	p.Asn1098Asn	synonymous_variant	Exon 21 of 23	1	NM_002693.3	ENSP00000268124.5		P54098

Frequencies

GnomAD3 genomes

AF:

0.000105

AC:

AN:

152196

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.000188

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000176

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000756

AC:

AN:

251390

Hom.:

AF XY:

0.0000589

AC XY:

AN XY:

135856

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:

0.000139

Gnomad NFE exome

AF:

0.000132

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000670

AC:

AN:

1461740

Hom.:

Cov.:

AF XY:

0.0000619

AC XY:

AN XY:

727180

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:

0.0000116

Gnomad4 FIN exome

AF:

0.000131

Gnomad4 NFE exome

AF:

0.0000791

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.000105

AC:

AN:

152196

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74356

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000188

Gnomad4 NFE

AF:

0.000176

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.0000989

Hom.:

Bravo

AF:

0.0000416

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1Benign:5

Revision: reviewed by expert panel

LINK: link

Submissions by phenotype

not specified

Benign:2

May 19, 2014

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Progressive sclerosing poliodystrophy

Benign:2

Oct 01, 2018

Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The NM_002693.2:c.3294T>C (NP_002684.1:p.Asn1098=) [GRCH38: NC_000015.10:g.89318729A>G] variant in POLG gene is interpretated to be a Likely Benign based on ACMG guidelines (PMID: 25741868). This variant meets the following evidence codes reported in the ACMG-guideline. BS1:The minor allele frequency of this allele is high for Mitochondrial DNA depletion syndrome 4A (Alpers type). BP4:Computational evidence/predictors indicate no impact on the POLG structure, function, or protein-protein interaction. BP7:The variant is silent with non predicted splice impact. Based on the evidence criteria codes applied, the variant is suggested to be Likely Benign. -

Dec 09, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mitochondrial disease

Uncertain:1

May 06, 2021

ClinGen Mitochondrial Disease Nuclear and Mitochondrial Variant Curation Expert Panel, ClinGen

Significance: Uncertain significance

Review Status: reviewed by expert panel

Collection Method: curation

The c.3294T>C (p.Asn1098=) variant in POLG is present in population databases at the following frequencies: gnomAD Allele Frequency: 0.00028 with 0 homozygotes (PM2). This is a silent variant and no change in the amino acid (BP7). It has not been published in the literature. In summary, there is insufficient evidence to characterize this variant and therefore it remains a variant of uncertain significance for primary mitochondrial disease inherited in an autosomal recessive manner. ntDNA Mitochondrial ACMG-AMP Criteria for POLG applied: PM2, BP7 -

not provided

Benign:1

Feb 01, 2025

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

POLG: BP4, BP7 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.62

CADD

Benign

7.4

DANN

Benign

0.76

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

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