15-89323460-C-T

Variant names:

• chr15-89323460-C-T
• rs121918054
• NM_002693.3:c.2209G>A

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PS1 PM2 PP3_Strong PP5

The NM_002693.3(POLG):​c.2209G>A​(p.Gly737Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,768 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 Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in Lovd.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: POLG NM_002693.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 6.01

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PS1: Transcript NM_002693.3 (POLG) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.963
• PP5: Variant 15-89323460-C-T is Pathogenic according to our data. Variant chr15-89323460-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 594491.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POLG	NM_002693.3	c.2209G>A	p.Gly737Arg	missense_variant	Exon 13 of 23	ENST00000268124.11	NP_002684.1
POLG	NM_001126131.2	c.2209G>A	p.Gly737Arg	missense_variant	Exon 13 of 23		NP_001119603.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POLG	ENST00000268124.11	c.2209G>A	p.Gly737Arg	missense_variant	Exon 13 of 23	1	NM_002693.3	ENSP00000268124.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251378 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135880

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461768 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727200

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Progressive sclerosing poliodystrophy;C1834846:Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1;C1843851:Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis;C3150914:Mitochondrial DNA depletion syndrome 4b;C4225153:Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1 Pathogenic:1

Jan 31, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Oct 16, 2017

Eurofins Ntd Llc (ga)

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.73	D;D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.96	.;D
M_CAP	Pathogenic	0.39	D
MetaRNN	Pathogenic	0.96	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	M;M
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-4.7	D;D
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0030	D;D
Polyphen		1.0	D;D
Vest4		0.87
MutPred		0.86		Loss of sheet (P = 0.1907);Loss of sheet (P = 0.1907);
MVP		0.98
MPC		0.72
ClinPred		0.99	D
GERP RS		5.6
Varity_R		0.64
gMVP		0.90

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

LitVar

Other links and lift over

dbSNP: rs121918054; hg19: chr15-89866691;