rs879135314

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PP3_Moderate

The NM_002693.3(POLG):​c.3445G>A​(p.Ala1149Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000322 in 1,613,796 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

POLG
NM_002693.3 missense

Scores

10
6
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 7.39
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1
In a helix (size 22) in uniprot entity DPOG1_HUMAN there are 5 pathogenic changes around while only 1 benign (83%) in NM_002693.3
PP3
MetaRNN computational evidence supports a deleterious effect, 0.884

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
POLGNM_002693.3 linkuse as main transcriptc.3445G>A p.Ala1149Thr missense_variant 21/23 ENST00000268124.11
POLGARFNM_001406557.1 linkuse as main transcriptc.*2717G>A 3_prime_UTR_variant 21/23
POLGNM_001126131.2 linkuse as main transcriptc.3445G>A p.Ala1149Thr missense_variant 21/23

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
POLGENST00000268124.11 linkuse as main transcriptc.3445G>A p.Ala1149Thr missense_variant 21/231 NM_002693.3 P1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152192
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251362
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135880
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000328
AC:
48
AN:
1461604
Hom.:
0
Cov.:
32
AF XY:
0.0000275
AC XY:
20
AN XY:
727106
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:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000396
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152192
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74358
show subpopulations
Gnomad4 AFR
AF:
0.0000241
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:
0.0000441
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:4
Uncertain significance, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicSep 17, 2021- -
Uncertain significance, criteria provided, single submitterclinical testingAthena DiagnosticsJun 22, 2023Available data are insufficient to determine the clinical significance of the variant at this time. The frequency of this variant in the general population is uninformative in assessment of its pathogenicity (http://gnomad.broadinstitute.org). Computational tools predict that this variant is damaging. -
Uncertain significance, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenMar 01, 2022POLG: PM1, PM2, PP3 -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxAug 28, 2023Reported in an individual with multiple sclerosis but did not segregate with disease in the family (Traboulsee et al., 2017); Not observed at 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: 28337550) -
Progressive sclerosing poliodystrophy Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingInvitaeJan 17, 2024This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1149 of the POLG protein (p.Ala1149Thr). This variant is present in population databases (no rsID available, gnomAD 0.004%). 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: 586360). 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 with a positive predictive value of 95%. 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
0.45
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.44
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.90
D;D
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.76
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Pathogenic
0.99
.;D
M_CAP
Uncertain
0.25
D
MetaRNN
Pathogenic
0.88
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Benign
2.0
M;M
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.74
T
PROVEAN
Uncertain
-3.6
D;D
REVEL
Pathogenic
0.84
Sift
Uncertain
0.0040
D;D
Sift4G
Benign
0.087
T;T
Polyphen
1.0
D;D
Vest4
0.75
MutPred
0.59
Gain of phosphorylation at A1149 (P = 0.1365);Gain of phosphorylation at A1149 (P = 0.1365);
MVP
0.99
MPC
0.65
ClinPred
1.0
D
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.70
gMVP
0.83

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.

Other links and lift over

dbSNP: rs879135314; hg19: chr15-89861809; API