rs754202777

chr15-89320808-T-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4

The NM_002693.3(POLG):c.2939A>C(p.Glu980Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,796 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 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

POLG
NM_002693.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.46

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:

POLGARF (HGNC:):

POLGARF links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.2678728).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
POLG	NM_002693.3 linkuse as main transcript	c.2939A>C	p.Glu980Ala	missense_variant	18/23	ENST00000268124.11
POLGARF	NM_001406557.1 linkuse as main transcript	c.*2211A>C		3_prime_UTR_variant	18/23
POLG	NM_001126131.2 linkuse as main transcript	c.2939A>C	p.Glu980Ala	missense_variant	18/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLG	ENST00000268124.11 linkuse as main transcript	c.2939A>C	p.Glu980Ala	missense_variant	18/23	1	NM_002693.3	P1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152216

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

250966

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135692

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:

0.0000440

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000192

AC:

AN:

1461580

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727076

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.0000383

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000243

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152216

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74376

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000151

Hom.:

Bravo

AF:

0.00000378

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

POLG-Related Spectrum Disorders

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Athena Diagnostics

Jan 11, 2018

- -

Progressive sclerosing poliodystrophy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 05, 2022

This sequence change replaces glutamic acid, which is acidic and polar, with alanine, which is neutral and non-polar, at codon 980 of the POLG protein (p.Glu980Ala). This variant is present in population databases (rs754202777, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with POLG-related conditions. ClinVar contains an entry for this variant (Variation ID: 528381). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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

Benign

0.098

BayesDel_addAF

Uncertain

0.069

BayesDel_noAF

Uncertain

-0.030

Cadd

Uncertain

Dann

Benign

0.87

DEOGEN2

Uncertain

0.62

D;D

Eigen

Benign

-0.14

Eigen_PC

Benign

0.032

FATHMM_MKL

Uncertain

0.90

M_CAP

Uncertain

0.15

MetaRNN

Benign

0.27

T;T

MetaSVM

Pathogenic

0.88

MutationAssessor

Benign

1.1

L;L

MutationTaster

Benign

1.0

D;D

PrimateAI

Benign

0.38

PROVEAN

Benign

-1.1

N;N

REVEL

Uncertain

0.43

Sift

Benign

0.63

T;T

Sift4G

Benign

0.77

T;T

Polyphen

0.17

B;B

Vest4

0.28

MutPred

0.42

Gain of MoRF binding (P = 0.0434);Gain of MoRF binding (P = 0.0434);

MVP

0.93

MPC

0.29

ClinPred

0.19

GERP RS

5.2

Varity_R

0.23

gMVP

0.45

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.070

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