rs753864625

chr15-89317514-C-Gchr15-89317514-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_002693.3(POLG):c.3505G>C(p.Gly1169Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1169S) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: POLG NM_002693.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.50

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]

POLGARF (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 11 uncertain in NM_002693.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.938

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POLG	NM_002693.3	c.3505G>C	p.Gly1169Arg	missense_variant	22/23	ENST00000268124.11
POLGARF	NM_001406557.1	c.*2777G>C		3_prime_UTR_variant	22/23
POLG	NM_001126131.2	c.3505G>C	p.Gly1169Arg	missense_variant	22/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POLG	ENST00000268124.11	c.3505G>C	p.Gly1169Arg	missense_variant	22/23	1	NM_002693.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000225 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
Cadd	Pathogenic	27
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D;D
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Pathogenic	0.63	D
MetaRNN	Pathogenic	0.94	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-6.3	D;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.0030	D;D
Polyphen		1.0	D;D
Vest4		0.86
MutPred		0.67		Gain of solvent accessibility (P = 0.0055);Gain of solvent accessibility (P = 0.0055);
MVP		0.98
MPC		0.72
ClinPred		1.0	D
GERP RS		3.8
Varity_R		0.89
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

Other links and lift over

dbSNP: rs753864625; hg19: chr15-89860745;