15-89323851-G-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong

The NM_002693.3(POLG):​c.2121C>A​(p.Asn707Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000359 in 1,614,136 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000038 ( 0 hom. )

Consequence

POLG
NM_002693.3 missense

Scores

2
17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: 0.258
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 Likely_benign. Variant got -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.054454386).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
POLGNM_002693.3 linkuse as main transcriptc.2121C>A p.Asn707Lys missense_variant 12/23 ENST00000268124.11 NP_002684.1
POLGARFNM_001406557.1 linkuse as main transcriptc.*1393C>A 3_prime_UTR_variant 12/23 NP_001393486.1
POLGNM_001126131.2 linkuse as main transcriptc.2121C>A p.Asn707Lys missense_variant 12/23 NP_001119603.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
POLGENST00000268124.11 linkuse as main transcriptc.2121C>A p.Asn707Lys missense_variant 12/231 NM_002693.3 ENSP00000268124 P1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152210
Hom.:
0
Cov.:
33
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:
0.000193
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
GnomAD3 exomes
AF:
0.0000398
AC:
10
AN:
251450
Hom.:
0
AF XY:
0.0000441
AC XY:
6
AN XY:
135908
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000791
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000376
AC:
55
AN:
1461808
Hom.:
0
Cov.:
32
AF XY:
0.0000454
AC XY:
33
AN XY:
727208
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000756
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000441
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152328
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74490
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000565
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000494
AC:
6
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingGeneDxFeb 26, 2024Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function -
Uncertain significance, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenJan 01, 2023- -
Progressive sclerosing poliodystrophy Uncertain:1Benign:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 19, 2022This sequence change replaces asparagine, which is neutral and polar, with lysine, which is basic and polar, at codon 707 of the POLG protein (p.Asn707Lys). This variant is present in population databases (rs755502359, gnomAD 0.008%). 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: 380291). 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 not expected to disrupt POLG protein function. 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. -
Likely benign, criteria provided, single submitterclinical testingWong Mito Lab, Molecular and Human Genetics, Baylor College of MedicineOct 01, 2018The NM_002693.2:c.2121C>A (NP_002684.1:p.Asn707Lys) [GRCH38: NC_000015.10:g.89323851G>T] 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. BP6:Reputable source(s) without shared data suggest the variant is benign. Based on the evidence criteria codes applied, the variant is suggested to be Likely Benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
2.0
DANN
Benign
0.62
DEOGEN2
Benign
0.24
T;T
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.2
FATHMM_MKL
Benign
0.28
N
LIST_S2
Benign
0.51
.;T
M_CAP
Benign
0.061
D
MetaRNN
Benign
0.054
T;T
MetaSVM
Uncertain
0.31
D
MutationAssessor
Uncertain
2.5
M;M
MutationTaster
Benign
1.0
N;N
PrimateAI
Benign
0.43
T
PROVEAN
Benign
0.27
N;N
REVEL
Benign
0.22
Sift
Benign
0.56
T;T
Sift4G
Benign
0.93
T;T
Polyphen
0.0
B;B
Vest4
0.13
MutPred
0.32
Gain of ubiquitination at N707 (P = 0.009);Gain of ubiquitination at N707 (P = 0.009);
MVP
0.57
MPC
0.18
ClinPred
0.023
T
GERP RS
1.3
Varity_R
0.044
gMVP
0.28

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs755502359; hg19: chr15-89867082; API