rs796052906

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM5PP3_StrongPP5_Very_Strong

The NM_002693.3(POLG):c.1943C>G(p.Pro648Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00001 in 1,600,416 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P648S) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

POLG
NM_002693.3 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.82

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 Pathogenic. Variant got 14 ACMG points.

PM5

Other missense variant is known to change same aminoacid residue: Variant chr15-89325456-GG-CT is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2861732.Status of the report is criteria_provided_single_submitter, 1 stars.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.978

PP5

Variant 15-89325456-G-C is Pathogenic according to our data. Variant chr15-89325456-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 206606.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr15-89325456-G-C is described in Lovd as [Pathogenic]. Variant chr15-89325456-G-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
POLG	NM_002693.3 linkuse as main transcript	c.1943C>G	p.Pro648Arg	missense_variant	10/23	ENST00000268124.11
POLGARF	NM_001406557.1 linkuse as main transcript	c.*1215C>G		3_prime_UTR_variant	10/23
POLG	NM_001126131.2 linkuse as main transcript	c.1943C>G	p.Pro648Arg	missense_variant	10/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLG	ENST00000268124.11 linkuse as main transcript	c.1943C>G	p.Pro648Arg	missense_variant	10/23	1	NM_002693.3	P1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152164

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:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000826

AC:

AN:

242174

Hom.:

AF XY:

0.0000152

AC XY:

AN XY:

131690

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.00000888

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000104

AC:

AN:

1448252

Hom.:

Cov.:

AF XY:

0.0000111

AC XY:

AN XY:

721076

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

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:

0.0000117

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152164

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74322

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:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Progressive sclerosing poliodystrophy

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 11, 2023	This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 648 of the POLG protein (p.Pro648Arg). This variant is present in population databases (rs796052906, gnomAD 0.003%). This missense change has been observed in individuals with autosomal recessive progressive external ophthalmoplegia (PEO) and/or sensory ataxia, neuropathy, dysarthria, and ophthalmoparesis (SANDO) syndrome (PMID: 16621917, 21550804). ClinVar contains an entry for this variant (Variation ID: 206606). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt POLG protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 09, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine	Oct 01, 2018	The NM_002693.2:c.1943C>G (NP_002684.1:p.Pro648Arg) [GRCH38: NC_000015.10:g.89325456G>C] variant in POLG gene is interpretated to be a Pathogenic based on ACMG guidelines (PMID: 25741868). This variant has been reported in PMID:21550804 . This variant meets the following evidence codes reported in the ACMG-guideline. PS1:This variation causes same amino-acid change as an established pathogenic variant. PS4:Prevalence of variant in affecteds statistically increased over controls. PM2:This variant is absent in key population databases. PM3:Detected in trans with a pathogenic variant for Mitochondrial DNA depletion syndrome 4A (Alpers type) which is a recessive disorder. PP1:This variant is co-segregated with Mitochondrial DNA depletion syndrome 4A (Alpers type) in multiple affected family members. PP2:This is a missense variant in POLG with a low rate of benign and high rate of pathogenic missense variations. PP4:Patient's phenotype or family history is highly specific for POLG. Based on the evidence criteria codes applied, the variant is suggested to be Pathogenic. -

Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

MGZ Medical Genetics Center

Dec 29, 2021

- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Apr 25, 2023

Not observed at a significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 21550804, 29358615, 32488467, 16919951, 25203713, 28130605, 16621917) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.86

BayesDel_addAF

Pathogenic

0.50

BayesDel_noAF

Pathogenic

0.56

Cadd

Pathogenic

Dann

Uncertain

1.0

DEOGEN2

Uncertain

0.74

D;D

Eigen

Pathogenic

0.78

Eigen_PC

Pathogenic

0.74

FATHMM_MKL

Uncertain

0.96

M_CAP

Pathogenic

0.62

MetaRNN

Pathogenic

0.98

D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.8

M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.60

PROVEAN

Pathogenic

-4.9

D;D

REVEL

Pathogenic

0.98

Sift

Uncertain

0.0010

D;D

Sift4G

Uncertain

0.0020

D;D

Polyphen

1.0

D;D

Vest4

0.91

MutPred

0.85

Gain of MoRF binding (P = 0.0186);Gain of MoRF binding (P = 0.0186);

MVP

0.99

MPC

0.68

ClinPred

0.99

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.85

gMVP

0.91

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