chr15-89330263-T-C
Position:
Variant summary
Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate
The NM_002693.3(POLG):c.673A>G(p.Ser225Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
Frequency
Genomes: not found (cov: 32)
Consequence
POLG
NM_002693.3 missense
NM_002693.3 missense
Scores
7
2
1
Clinical Significance
Conservation
PhyloP100: 7.92
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]
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]
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ACMG classification
Classification made for transcript
Verdict is Uncertain_significance. Variant got 4 ACMG points.
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.877
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
POLG | NM_002693.3 | c.673A>G | p.Ser225Gly | missense_variant | 3/23 | ENST00000268124.11 | NP_002684.1 | |
POLGARF | NM_001406557.1 | c.728A>G | p.Gln243Arg | missense_variant | 3/23 | NP_001393486.1 | ||
POLG | NM_001126131.2 | c.673A>G | p.Ser225Gly | missense_variant | 3/23 | NP_001119603.1 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
POLG | ENST00000268124.11 | c.673A>G | p.Ser225Gly | missense_variant | 3/23 | 1 | NM_002693.3 | ENSP00000268124 | P1 | |
POLGARF | ENST00000706918.1 | c.728A>G | p.Gln243Arg | missense_variant | 2/2 | ENSP00000516626 | P1 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD3 genomes
Cov.:
32
GnomAD4 exome Cov.: 32
GnomAD4 exome
Cov.:
32
GnomAD4 genome Cov.: 32
GnomAD4 genome
Cov.:
32
ClinVar
Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link
Submissions by phenotype
Progressive sclerosing poliodystrophy Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Labcorp Genetics (formerly Invitae), Labcorp | Jul 31, 2023 | 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. 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. This variant has not been reported in the literature in individuals affected with POLG-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with glycine, which is neutral and non-polar, at codon 225 of the POLG protein (p.Ser225Gly). - |
Computational scores
Source:
Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
BayesDel_addAF
Pathogenic
D
BayesDel_noAF
Pathogenic
CADD
Pathogenic
DANN
Uncertain
Eigen
Pathogenic
Eigen_PC
Pathogenic
FATHMM_MKL
Pathogenic
D
M_CAP
Uncertain
D
MetaRNN
Pathogenic
D
MutationTaster
Benign
D;D
ClinPred
D
GERP RS
RBP_binding_hub_radar
RBP_regulation_power_radar
Splicing
Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
Details are displayed if max score is > 0.2
Find out detailed SpliceAI scores and Pangolin per-transcript scores at
Publications
No publications associated with this variant yet.