rs768653086
Variant summary
Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1
The NM_002693.3(POLG):c.2830G>A(p.Glu944Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000204 in 1,613,882 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E944G) has been classified as Uncertain significance.
Frequency
Consequence
NM_002693.3 missense
Scores
Clinical Significance
Conservation
Publications
- progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
- mitochondrial DNA depletion syndrome 4aInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet, G2P
- sensory ataxic neuropathy, dysarthria, and ophthalmoparesisInheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P
- autosomal dominant progressive external ophthalmoplegiaInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- autosomal recessive progressive external ophthalmoplegiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- mitochondrial neurogastrointestinal encephalomyopathyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- recessive mitochondrial ataxia syndromeInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- spinocerebellar ataxia with epilepsyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Leigh syndromeInheritance: AR Classification: LIMITED Submitted by: ClinGen
Genome browser will be placed here
ACMG classification
Our verdict: Uncertain_significance. The variant received 2 ACMG points.
Transcripts
RefSeq
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| POLG | ENST00000268124.11 | c.2830G>A | p.Glu944Lys | missense_variant | Exon 18 of 23 | 1 | NM_002693.3 | ENSP00000268124.5 |
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152222Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.000167 AC: 42AN: 251170 AF XY: 0.0000589 show subpopulations
GnomAD4 exome AF: 0.0000198 AC: 29AN: 1461660Hom.: 0 Cov.: 35 AF XY: 0.0000151 AC XY: 11AN XY: 727144 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152222Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1AN XY: 74378 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not provided Uncertain:2
- -
In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -
Progressive sclerosing poliodystrophy Uncertain:2
The NM_002693.2:c.2830G>A (NP_002684.1:p.Glu944Lys) [GRCH38: NC_000015.10:g.89320917C>T] variant in POLG gene is interpretated to be a Uncertain Significance based on ACMG guidelines (PMID: 25741868). This variant meets the following evidence codes reported in the ACMG-guideline. PM1:This variant is in mutational hot spot or a well-studied functional domain without benign variation. PM2:This variant is absent in key population databases. Based on the evidence criteria codes applied, the variant is suggested to be Uncertain Significance. -
This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 944 of the POLG protein (p.Glu944Lys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with POLG-related conditions (PMID: 34573359). ClinVar contains an entry for this variant (Variation ID: 206535). 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. -
POLG-Related Spectrum Disorders Uncertain:1
This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -
Inborn genetic diseases Uncertain:1
The p.E944K variant (also known as c.2830G>A), located in coding exon 17 of the POLG gene, results from a G to A substitution at nucleotide position 2830. The glutamic acid at codon 944 is replaced by lysine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at