15-89317446-C-G

Variant names:

• chr15-89317446-C-G
• NM_002693.3:c.3573G>C
• POLG p.Lys1191Asn

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PS1_Very_Strong PM1 PM2 PP3_Strong

The NM_002693.3(POLG):​c.3573G>C​(p.Lys1191Asn) variant causes a missense change involving the alteration of a non-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 nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K1191R) has been classified as Uncertain significance. The gene POLG is included in the ClinGen Criteria Specification Registry.

• Frequency: Genomes: not found (cov: 32)
• Consequence: POLG NM_002693.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.787
• Publications: 0 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]

FANCI (HGNC:25568): (FA complementation group I) The Fanconi anemia complementation group (FANC) currently includes FANCA, FANCB, FANCC, FANCD1 (also called BRCA2), FANCD2, FANCE, FANCF, FANCG, FANCI, FANCJ (also called BRIP1), FANCL, FANCM and FANCN (also called PALB2). The previously defined group FANCH is the same as FANCA. Fanconi anemia is a genetically heterogeneous recessive disorder characterized by cytogenetic instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group I. Alternative splicing results in two transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

FANCI Gene-Disease associations (from GenCC):

• Fanconi anemia complementation group I

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Specifications for POLG are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PS1: Transcript NM_002693.3 (POLG) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 15 uncertain in NM_002693.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLG	NM_002693.3	MANE Select	c.3573G>C	p.Lys1191Asn	missense	Exon 22 of 23	NP_002684.1	P54098
	POLG	NM_001126131.2		c.3573G>C	p.Lys1191Asn	missense	Exon 22 of 23	NP_001119603.1	P54098
	FANCI	NM_018193.3		c.*987C>G		downstream_gene	N/A	NP_060663.2	Q9NVI1-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POLG	ENST00000268124.11	TSL:1 MANE Select	c.3573G>C	p.Lys1191Asn	missense	Exon 22 of 23	ENSP00000268124.5	P54098
	POLG	ENST00000442287.6	TSL:1	c.3573G>C	p.Lys1191Asn	missense	Exon 22 of 23	ENSP00000399851.2	P54098
	POLG	ENST00000636937.2	TSL:5	c.3573G>C	p.Lys1191Asn	missense	Exon 22 of 23	ENSP00000516154.1	P54098

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.26
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.44	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.5	H
PhyloP100		0.79
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Varity_R		0.94
gMVP		0.95

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr15-89860677;