chr8-76984088-G-A

Variant names:

• chr8-76984088-G-A
• rs149287302
• NM_000318.3:c.91C>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000318.3(PEX2):​c.91C>T​(p.Gln31*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,460,260 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 Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. Q31Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PEX2 NM_000318.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.64
• Publications: 3 publications found

Genes affected

PEX2 (HGNC:9717): (peroxisomal biogenesis factor 2) This gene encodes an integral peroxisomal membrane protein required for peroxisome biogenesis. The protein is thought to be involved in peroxisomal matrix protein import. Mutations in this gene result in one form of Zellweger syndrome and infantile Refsum disease. Alternative splicing results in multiple transcript variants encoding the same protein. [provided by RefSeq, Jul 2008]

PEX2 Gene-Disease associations (from GenCC):

• peroxisome biogenesis disorder

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• peroxisome biogenesis disorder 5A (Zellweger)

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health, G2P
• peroxisome biogenesis disorder 5B

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Zellweger spectrum disorders

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 74 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-76984088-G-A is Pathogenic according to our data. Variant chr8-76984088-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 1454128.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000318.3. 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
	PEX2	NM_000318.3	MANE Select	c.91C>T	p.Gln31*	stop_gained	Exon 4 of 4	NP_000309.2
	PEX2	NM_001079867.2		c.91C>T	p.Gln31*	stop_gained	Exon 3 of 3	NP_001073336.2
	PEX2	NM_001172086.2		c.91C>T	p.Gln31*	stop_gained	Exon 5 of 5	NP_001165557.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PEX2	ENST00000357039.9	TSL:1 MANE Select	c.91C>T	p.Gln31*	stop_gained	Exon 4 of 4	ENSP00000349543.4
	PEX2	ENST00000522527.5	TSL:1	c.91C>T	p.Gln31*	stop_gained	Exon 3 of 3	ENSP00000428638.1
	PEX2	ENST00000520103.5	TSL:2	c.91C>T	p.Gln31*	stop_gained	Exon 3 of 3	ENSP00000428590.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152098 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 250288 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1460260 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 726314

African (AFR) AF: 0.00 AC: 0 AN: 33356

American (AMR) AF: 0.00 AC: 0 AN: 44528

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26012

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.0000349 AC: 3 AN: 86074

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53366

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5752

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111192

Other (OTH) AF: 0.00 AC: 0 AN: 60292

GnomAD4 genome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000657 AC: 1 AN: 152098 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74292

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41410

American (AMR) AF: 0.00 AC: 0 AN: 15266

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5190

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10598

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Peroxisome biogenesis disorder 5A (Zellweger) Pathogenic:1

Jun 04, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the PEX2 protein in which other variant(s) (p.Lys215Serfs*2) have been determined to be pathogenic (PMID: 10652207; Invitae). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. ClinVar contains an entry for this variant (Variation ID: 1454128). This variant has not been reported in the literature in individuals affected with PEX2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change creates a premature translational stop signal (p.Gln31*) in the PEX2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 275 amino acid(s) of the PEX2 protein.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	38
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		7.6
Vest4		0.83
GERP RS		5.7
Mutation Taster		=9/191	disease causing

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

Other links and lift over

dbSNP: rs149287302; hg19: chr8-77896324; COSMIC: COSV63813215; COSMIC: COSV63813215;