rs558958919

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 4P and 10B. PM1PM2BP4_ModerateBP6_Very_Strong

The ENST00000706918.1(POLGARF):​c.439G>T​(p.Ala147Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000571 in 1,576,876 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 8/10 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A147P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000049 ( 0 hom. )

Consequence

POLGARF
ENST00000706918.1 missense

Scores

6

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: 0.264

Publications

0 publications found
Variant links:
Genes affected
POLGARF (HGNC:56246): (POLG alternative reading frame) This gene uses the same transcript as the POLG gene but has a CUG start codon and an alternate reading frame that makes a 260 aa protein. This protein is distinct from POLG isoforms and may interact with P32 (also known as C1QBP), a mitochondrial matrix protein thought to be involved in the expression of mitochondrial genome-encoded proteins. POLGARF protein may bind P32 and sequester it in the nucleolus. Interestingly, some disease-causing mutations thought to be in POLG may instead be associated with POLGARF. [provided by RefSeq, May 2022]
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 Gene-Disease associations (from GenCC):
  • progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • mitochondrial DNA depletion syndrome 4a
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • sensory ataxic neuropathy, dysarthria, and ophthalmoparesis
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P
  • autosomal dominant progressive external ophthalmoplegia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive progressive external ophthalmoplegia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • mitochondrial neurogastrointestinal encephalomyopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • recessive mitochondrial ataxia syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • spinocerebellar ataxia with epilepsy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Leigh syndrome
    Inheritance: AR Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 13 benign, 17 uncertain in ENST00000706918.1
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.14833647).
BP6
Variant 15-89333371-C-A is Benign according to our data. Variant chr15-89333371-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 381383.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POLGNM_002693.3 linkc.384G>T p.Pro128Pro synonymous_variant Exon 2 of 23 ENST00000268124.11 NP_002684.1 P54098E5KNU5
POLGARFNM_001430120.1 linkc.439G>T p.Ala147Ser missense_variant Exon 1 of 2 NP_001417049.1
POLGNM_001126131.2 linkc.384G>T p.Pro128Pro synonymous_variant Exon 2 of 23 NP_001119603.1 P54098E5KNU5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POLGARFENST00000706918.1 linkc.439G>T p.Ala147Ser missense_variant Exon 1 of 2 ENSP00000516626.1 A0A3B3IS91
POLGENST00000268124.11 linkc.384G>T p.Pro128Pro synonymous_variant Exon 2 of 23 1 NM_002693.3 ENSP00000268124.5 P54098

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152252
Hom.:
0
Cov.:
34
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000534
AC:
1
AN:
187310
AF XY:
0.00000975
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000126
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000491
AC:
7
AN:
1424624
Hom.:
0
Cov.:
32
AF XY:
0.00000283
AC XY:
2
AN XY:
706394
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32638
American (AMR)
AF:
0.00
AC:
0
AN:
40240
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25438
East Asian (EAS)
AF:
0.00
AC:
0
AN:
37598
South Asian (SAS)
AF:
0.00
AC:
0
AN:
82908
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
44702
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5666
European-Non Finnish (NFE)
AF:
0.00000638
AC:
7
AN:
1096458
Other (OTH)
AF:
0.00
AC:
0
AN:
58976
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152252
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74386
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000302

ClinVar

Significance: Likely benign
Submissions summary: Benign:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

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.384G>T (NP_002684.1:p.Pro128=) [GRCH38: NC_000015.10:g.89333371C>A] 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. 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. -

Jan 11, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Nov 10, 2015
GeneDx
Significance:Likely 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.20
BayesDel_noAF
Benign
-0.37
CADD
Benign
17
DANN
Benign
0.87
FATHMM_MKL
Benign
0.68
D
MetaRNN
Benign
0.15
T
PhyloP100
0.26
GERP RS
0.51
PromoterAI
0.060
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=100/0
polymorphism

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

Other links and lift over

dbSNP: rs558958919; hg19: chr15-89876602; COSMIC: COSV51522878; COSMIC: COSV51522878; API