rs371431444

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_002693.3(POLG):​c.1066C>T​(p.Leu356Leu) variant causes a synonymous change. The variant allele was found at a frequency of 0.0000843 in 1,614,152 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L356L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000081 ( 2 hom. )

Consequence

POLG
NM_002693.3 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:6

Conservation

PhyloP100: 5.65

Publications

0 publications found
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]
POLG Gene-Disease associations (from GenCC):
  • progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • mitochondrial DNA depletion syndrome 4a
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • sensory ataxic neuropathy, dysarthria, and ophthalmoparesis
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P
  • autosomal dominant progressive external ophthalmoplegia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive progressive external ophthalmoplegia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • mitochondrial neurogastrointestinal encephalomyopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • recessive mitochondrial ataxia syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • spinocerebellar ataxia with epilepsy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Leigh syndrome
    Inheritance: AR Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.4).
BP6
Variant 15-89328789-G-A is Benign according to our data. Variant chr15-89328789-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 138772.
BS2
High Homozygotes in GnomAdExome4 at 2 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POLGNM_002693.3 linkc.1066C>T p.Leu356Leu synonymous_variant Exon 5 of 23 ENST00000268124.11 NP_002684.1 P54098E5KNU5
POLGNM_001126131.2 linkc.1066C>T p.Leu356Leu synonymous_variant Exon 5 of 23 NP_001119603.1 P54098E5KNU5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POLGENST00000268124.11 linkc.1066C>T p.Leu356Leu synonymous_variant Exon 5 of 23 1 NM_002693.3 ENSP00000268124.5 P54098

Frequencies

GnomAD3 genomes
AF:
0.000118
AC:
18
AN:
152254
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000327
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000199
AC:
50
AN:
251342
AF XY:
0.000169
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00250
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000807
AC:
118
AN:
1461780
Hom.:
2
Cov.:
33
AF XY:
0.0000646
AC XY:
47
AN XY:
727180
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00111
AC:
44
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53318
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112002
Other (OTH)
AF:
0.00118
AC:
71
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
10
21
31
42
52
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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
GnomAD4 genome
AF:
0.000118
AC:
18
AN:
152372
Hom.:
0
Cov.:
32
AF XY:
0.000107
AC XY:
8
AN XY:
74512
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41588
American (AMR)
AF:
0.000327
AC:
5
AN:
15312
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00193
AC:
10
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68038
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
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:
0.000162
Hom.:
0
Bravo
AF:
0.000159
Asia WGS
AF:
0.00635
AC:
22
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:6
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:3
Jun 07, 2013
GeneDx
Significance: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. -

Jul 11, 2024
Athena Diagnostics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 03, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:2
Mar 01, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BP4 -

May 18, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Progressive sclerosing poliodystrophy Benign:2
Oct 01, 2018
Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The NM_002693.2:c.1066C>T (NP_002684.1:p.Leu356=) [GRCH38: NC_000015.10:g.89328789G>A] 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. BS1:The minor allele frequency of this allele is high for Mitochondrial DNA depletion syndrome 4A (Alpers type). BP4:Computational evidence/predictors indicate no impact on the POLG structure, function, or protein-protein interaction. BP7:The variant is silent with non predicted splice impact. Based on the evidence criteria codes applied, the variant is suggested to be Likely Benign. -

Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

POLG-Related Spectrum Disorders Uncertain:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Inborn genetic diseases Benign:1
Apr 11, 2018
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.40
CADD
Benign
9.5
DANN
Benign
0.75
PhyloP100
5.7
PromoterAI
0.021
Neutral
Mutation Taster
=49/51
disease causing

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

Other links and lift over

dbSNP: rs371431444; hg19: chr15-89872020; API