15-89318989-G-C

Variant names:

• chr15-89318989-G-C
• rs530757118
• NM_002693.3:c.3215C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PP3_Strong

The NM_002693.3(POLG):​c.3215C>G​(p.Thr1072Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,614,116 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 (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T1072I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: POLG NM_002693.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 9.37
• Publications: 1 publications found

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

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 uncertain in NM_002693.3
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.952

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002693.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLG	NM_002693.3	MANE Select	c.3215C>G	p.Thr1072Ser	missense	Exon 20 of 23	NP_002684.1
	POLG	NM_001126131.2		c.3215C>G	p.Thr1072Ser	missense	Exon 20 of 23	NP_001119603.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLG	ENST00000268124.11	TSL:1 MANE Select	c.3215C>G	p.Thr1072Ser	missense	Exon 20 of 23	ENSP00000268124.5
	POLG	ENST00000442287.6	TSL:1	c.3215C>G	p.Thr1072Ser	missense	Exon 20 of 23	ENSP00000399851.2
	POLG	ENST00000636937.2	TSL:5	c.3215C>G	p.Thr1072Ser	missense	Exon 20 of 23	ENSP00000516154.1

Frequencies

GnomAD3 genomes AF: 0.0000394 AC: 6 AN: 152128 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

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: 0.0000120 AC: 3 AN: 250906 AF XY: 0.0000147

Gnomad AFR exome AF: 0.0000617

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461870 Hom.: 0 Cov.: 32 AF XY: 0.00000963 AC XY: 7 AN XY: 727234

African (AFR) AF: 0.000119 AC: 4 AN: 33480

American (AMR) AF: 0.0000447 AC: 2 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1111998

Other (OTH) AF: 0.0000166 AC: 1 AN: 60394

GnomAD4 genome AF: 0.0000394 AC: 6 AN: 152246 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74438

African (AFR) AF: 0.000120 AC: 5 AN: 41534

American (AMR) AF: 0.00 AC: 0 AN: 15298

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4818

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68020

Other (OTH) AF: 0.000473 AC: 1 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000869

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	Progressive sclerosing poliodystrophy (2)
-	1	-	Inborn genetic diseases (1)
-	1	-	not provided (1)
-	1	-	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;C4551995:Mitochondrial DNA depletion syndrome 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.34
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.29	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.5	M
PhyloP100		9.4
PrimateAI	Uncertain	0.50	T
PROVEAN	Uncertain	-3.6	D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0080	D
Sift4G	Uncertain	0.015	D
Polyphen		1.0	D
Vest4		0.86
MutPred		0.85		Gain of disorder (P = 0.0633)
MVP		0.97
MPC		0.62
ClinPred		0.97	D
GERP RS		5.3
Varity_R		0.73
gMVP		0.82
Mutation Taster		=42/58	disease causing

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

Other links and lift over

dbSNP: rs530757118; hg19: chr15-89862220; COSMIC: COSV51523855; COSMIC: COSV51523855;