rs148101254

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_007215.4(POLG2):​c.674G>A​(p.Arg225Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000706 in 1,614,048 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R225G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00016 ( 1 hom., cov: 32)
Exomes 𝑓: 0.000061 ( 0 hom. )

Consequence

POLG2
NM_007215.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 0.0500

Publications

5 publications found
Variant links:
Genes affected
POLG2 (HGNC:9180): (DNA polymerase gamma 2, accessory subunit) This gene encodes the processivity subunit of the mitochondrial DNA polymerase gamma. The encoded protein forms a heterotrimer containing one catalytic subunit and two processivity subunits. This protein enhances DNA binding and promotes processive DNA synthesis. Mutations in this gene result in autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions.[provided by RefSeq, Sep 2009]
MILR1 (HGNC:27570): (mast cell immunoglobulin like receptor 1) Predicted to enable transmembrane signaling receptor activity. Predicted to be involved in several processes, including cell-cell adhesion via plasma-membrane adhesion molecules; mast cell degranulation; and negative regulation of mast cell activation. Predicted to be integral component of plasma membrane. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.017912477).
BP6
Variant 17-64492910-C-T is Benign according to our data. Variant chr17-64492910-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 324559.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POLG2NM_007215.4 linkc.674G>A p.Arg225Gln missense_variant Exon 2 of 8 ENST00000539111.7 NP_009146.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POLG2ENST00000539111.7 linkc.674G>A p.Arg225Gln missense_variant Exon 2 of 8 1 NM_007215.4 ENSP00000442563.2

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152144
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000507
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000795
AC:
20
AN:
251450
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.000677
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000609
AC:
89
AN:
1461786
Hom.:
0
Cov.:
31
AF XY:
0.0000591
AC XY:
43
AN XY:
727200
show subpopulations
African (AFR)
AF:
0.000478
AC:
16
AN:
33480
American (AMR)
AF:
0.0000894
AC:
4
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39686
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000477
AC:
53
AN:
1111936
Other (OTH)
AF:
0.000199
AC:
12
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
4
9
13
18
22
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.000164
AC:
25
AN:
152262
Hom.:
1
Cov.:
32
AF XY:
0.000161
AC XY:
12
AN XY:
74434
show subpopulations
African (AFR)
AF:
0.000505
AC:
21
AN:
41554
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000208
AC:
1
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.436
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000281
Hom.:
0
Bravo
AF:
0.000234
ESP6500AA
AF:
0.000908
AC:
4
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000824
AC:
10
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Nov 22, 2016
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 225 of the POLG2 protein (p.Arg225Gln). This variant is present in population databases (rs148101254, gnomAD 0.06%), and has an allele count higher than expected for a pathogenic variant. This variant has not been reported in the literature in individuals affected with POLG2-related conditions. ClinVar contains an entry for this variant (Variation ID: 324559). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. -

Hereditary spastic paraplegia Uncertain:1
Dec 12, 2016
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Dec 27, 2016
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. -

Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 4 Benign:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.066
BayesDel_addAF
Benign
-0.49
T
BayesDel_noAF
Benign
-0.57
CADD
Benign
12
DANN
Benign
0.81
DEOGEN2
Benign
0.094
T
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.3
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.64
T
M_CAP
Benign
0.049
D
MetaRNN
Benign
0.018
T
MetaSVM
Benign
-0.87
T
MutationAssessor
Benign
0.0
N
PhyloP100
0.050
PrimateAI
Benign
0.28
T
PROVEAN
Benign
-0.98
N
REVEL
Benign
0.15
Sift
Benign
0.60
T
Sift4G
Benign
0.61
T
Polyphen
0.0010
B
Vest4
0.23
MVP
0.74
MPC
0.15
ClinPred
0.0052
T
GERP RS
1.1
PromoterAI
0.017
Neutral
Varity_R
0.045
gMVP
0.12
Mutation Taster
=92/8
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs148101254; hg19: chr17-62489027; COSMIC: COSV73347032; COSMIC: COSV73347032; API