15-89330106-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_002693.3(POLG):ā€‹c.830A>Cā€‹(p.His277Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,800 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (ā˜…).

Frequency

Genomes: not found (cov: 32)
Exomes š‘“: 6.8e-7 ( 0 hom. )

Consequence

POLG
NM_002693.3 missense

Scores

5
9
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.41
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 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, 0.908

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
POLGNM_002693.3 linkuse as main transcriptc.830A>C p.His277Pro missense_variant 3/23 ENST00000268124.11 NP_002684.1
POLGARFNM_001406557.1 linkuse as main transcriptc.*102A>C 3_prime_UTR_variant 3/23 NP_001393486.1
POLGNM_001126131.2 linkuse as main transcriptc.830A>C p.His277Pro missense_variant 3/23 NP_001119603.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
POLGENST00000268124.11 linkuse as main transcriptc.830A>C p.His277Pro missense_variant 3/231 NM_002693.3 ENSP00000268124 P1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461800
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727212
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxApr 20, 2018The H277P variant in the POLG gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The H277P variant is not observed in large population cohorts (Lek et al., 2016). The H277P variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is not conserved. In silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret H277P as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.84
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.090
CADD
Uncertain
25
DANN
Uncertain
0.98
DEOGEN2
Pathogenic
0.80
D;D
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.90
.;D
M_CAP
Benign
0.081
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Uncertain
0.55
D
MutationAssessor
Uncertain
2.2
M;M
MutationTaster
Benign
1.0
D;D
PrimateAI
Benign
0.44
T
PROVEAN
Uncertain
-3.0
D;D
REVEL
Pathogenic
0.76
Sift
Benign
0.058
T;T
Sift4G
Benign
0.080
T;T
Polyphen
0.98
D;D
Vest4
0.75
MutPred
0.77
Gain of loop (P = 0.069);Gain of loop (P = 0.069);
MVP
0.98
MPC
0.74
ClinPred
0.93
D
GERP RS
4.5
Varity_R
0.82
gMVP
0.90

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs138929605; hg19: chr15-89873337; API