15-89333596-TTGCTGCTGCTGCTGCTGCTGCTGCTGCTGC-TTGCTGCTGCTGCTGCTGCTGCTGCTGC

Position:

• chr15-89333596-TTGCTGCTGCTGCTGCTGCTGCTGCTGCTGC-TTGCTGCTGCTGCTGCTGCTGCTGCTGC

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP3 BP6_Very_Strong BS2

The NM_001406557.1(POLGARF):​c.211_213delGCA​(p.Ala71del) variant causes a conservative inframe deletion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0109 in 1,579,960 control chromosomes in the GnomAD database, including 92 homozygotes. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0090 (5 hom., cov: 30)
  • Exomes 𝑓: 0.011 (87 hom.)
• Consequence: POLGARF NM_001406557.1 conservative_inframe_deletion
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:15
• Conservation: PhyloP100: 0.0750

Genes affected

POLGARF (HGNC:56246): (POLG alternative reading frame) This gene uses the same transcript as the POLG gene but has a CUG start codon and an alternate reading frame that makes a 260 aa protein. This protein is distinct from POLG isoforms and may interact with P32 (also known as C1QBP), a mitochondrial matrix protein thought to be involved in the expression of mitochondrial genome-encoded proteins. POLGARF protein may bind P32 and sequester it in the nucleolus. Interestingly, some disease-causing mutations thought to be in POLG may instead be associated with POLGARF. [provided by RefSeq, May 2022]

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 Benign. Variant got -13 ACMG points.

• BP3: Nonframeshift variant in repetitive region in NM_001406557.1
• BP6: Variant 15-89333596-TTGC-T is Benign according to our data. Variant chr15-89333596-TTGC-T is described in ClinVar as [Likely_benign]. Clinvar id is 167521.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr15-89333596-TTGC-T is described in Lovd as [Benign]. Variant chr15-89333596-TTGC-T is described in Lovd as [Benign].
• BS2: High Homozygotes in GnomAd4 at 5 gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POLG	NM_002693.3	c.156_158delGCA	p.Gln53del	disruptive_inframe_deletion	2/23	ENST00000268124.11	NP_002684.1
POLGARF	NM_001406557.1	c.211_213delGCA	p.Ala71del	conservative_inframe_deletion	2/23
POLG	NM_001126131.2	c.156_158delGCA	p.Gln53del	disruptive_inframe_deletion	2/23		NP_001119603.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POLGARF	ENST00000706918.1	c.211_213delGCA	p.Ala71del	conservative_inframe_deletion	1/2			ENSP00000516626.1
POLG	ENST00000268124.11	c.156_158delGCA	p.Gln53del	disruptive_inframe_deletion	2/23	1	NM_002693.3	ENSP00000268124.5

Frequencies

GnomAD3 genomes AF: 0.00902 AC: 1367 AN: 151586 Hom.: 5 Cov.: 30

Gnomad AFR AF: 0.00410

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00957

Gnomad ASJ AF: 0.00317

Gnomad EAS AF: 0.000966

Gnomad SAS AF: 0.00729

Gnomad FIN AF: 0.0245

Gnomad MID AF: 0.00633

Gnomad NFE AF: 0.0107

Gnomad OTH AF: 0.00771

GnomAD4 exome AF: 0.0111 AC: 15824 AN: 1428270 Hom.: 87 AF XY: 0.0110 AC XY: 7817 AN XY: 709892

Gnomad4 AFR exome AF: 0.00431

Gnomad4 AMR exome AF: 0.00861

Gnomad4 ASJ exome AF: 0.00599

Gnomad4 EAS exome AF: 0.00320

Gnomad4 SAS exome AF: 0.00935

Gnomad4 FIN exome AF: 0.0275

Gnomad4 NFE exome AF: 0.0113

Gnomad4 OTH exome AF: 0.0101

GnomAD4 genome AF: 0.00902 AC: 1369 AN: 151690 Hom.: 5 Cov.: 30 AF XY: 0.00933 AC XY: 692 AN XY: 74152

Gnomad4 AFR AF: 0.00414

Gnomad4 AMR AF: 0.00956

Gnomad4 ASJ AF: 0.00317

Gnomad4 EAS AF: 0.000969

Gnomad4 SAS AF: 0.00730

Gnomad4 FIN AF: 0.0245

Gnomad4 NFE AF: 0.0107

Gnomad4 OTH AF: 0.00763

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:15

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:7

Benign, criteria provided, single submitter	clinical testing	GeneDx	Jun 12, 2014	The variant is found in EPILEPSY,CHILD-EPI,MITONUC-MITOP panel(s). -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -
Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 12, 2014	- -
Benign, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Aug 04, 2016	- -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, Amsterdam University Medical Center	-	- -
Benign, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

not provided Benign:3

Benign, no assertion criteria provided	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jul 27, 2017	- -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 26, 2023	- -
Benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2024	POLG: BS1, BS2 -

Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1 Benign:1

Benign, criteria provided, single submitter

clinical testing

Molecular Genetics, Royal Melbourne Hospital

Oct 06, 2023

- -

Inborn genetic diseases Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 07, 2016

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Hereditary spastic paraplegia Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Nov 10, 2021

- -

POLG-related disorder Benign:1

Benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 27, 2020

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Progressive sclerosing poliodystrophy Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 01, 2024

- -

Computational scores

Source: dbNSFP v4.3

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: rs41550117; hg19: chr15-89876827;