22-18079908-G-A

Variant names:

• chr22-18079908-G-A
• rs28940308
• NM_001127649.3:c.265G>A

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_001127649.3(PEX26):​c.265G>A​(p.Gly89Arg) 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. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G89G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PEX26 NM_001127649.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 8.04
• Publications: 8 publications found

Genes affected

PEX26 (HGNC:22965): (peroxisomal biogenesis factor 26) This gene belongs to the peroxin-26 gene family. It is probably required for protein import into peroxisomes. It anchors PEX1 and PEX6 to peroxisome membranes, possibly to form heteromeric AAA ATPase complexes required for the import of proteins into peroxisomes. Defects in this gene are the cause of peroxisome biogenesis disorder complementation group 8 (PBD-CG8). PBD refers to a group of peroxisomal disorders arising from a failure of protein import into the peroxisomal membrane or matrix. The PBD group is comprised of four disorders: Zellweger syndrome (ZWS), neonatal adrenoleukodystrophy (NALD), infantile Refsum disease (IRD), and classical rhizomelic chondrodysplasia punctata (RCDP). Alternatively spliced transcript variants have been identified for this gene. [provided by RefSeq, Dec 2010]

PEX26 Gene-Disease associations (from GenCC):

• peroxisome biogenesis disorder

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• peroxisome biogenesis disorder 7A (Zellweger)

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• peroxisome biogenesis disorder 7B

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P
• Zellweger spectrum disorders

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000288683 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 22-18079908-G-A is Pathogenic according to our data. Variant chr22-18079908-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2153.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PEX26	NM_001127649.3	c.265G>A	p.Gly89Arg	missense_variant	Exon 2 of 5	ENST00000399744.8	NP_001121121.1
PEX26	NM_017929.6	c.265G>A	p.Gly89Arg	missense_variant	Exon 3 of 6		NP_060399.1
PEX26	NM_001199319.2	c.265G>A	p.Gly89Arg	missense_variant	Exon 3 of 5		NP_001186248.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PEX26	ENST00000399744.8	c.265G>A	p.Gly89Arg	missense_variant	Exon 2 of 5	1	NM_001127649.3	ENSP00000382648.4
PEX26	ENST00000329627.11	c.265G>A	p.Gly89Arg	missense_variant	Exon 3 of 6	1		ENSP00000331106.5
PEX26	ENST00000428061.2	c.265G>A	p.Gly89Arg	missense_variant	Exon 2 of 4	1		ENSP00000412441.2
ENSG00000288683	ENST00000474897.6	n.265G>A		non_coding_transcript_exon_variant	Exon 3 of 9	5		ENSP00000434235.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Peroxisome biogenesis disorder 7A (Zellweger) Pathogenic:2

Feb 01, 2023

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 01, 2003

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Peroxisome biogenesis disorder 7B;C3888385:Peroxisome biogenesis disorder 7A (Zellweger) Pathogenic:1

Feb 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 89 of the PEX26 protein (p.Gly89Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Zellweger syndrome (PMID: 12851857). ClinVar contains an entry for this variant (Variation ID: 2153). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PEX26 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects PEX26 function (PMID: 12851857). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.70	.;D;D;.
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.95	D;.;D;.
M_CAP	Pathogenic	0.43	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M;M;M;M
PhyloP100		8.0
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-6.3	.;D;D;D
REVEL	Pathogenic	0.97
Sift	Uncertain	0.0020	.;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	.;D;D;.
Vest4		1.0
MutPred		0.97		Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);
MVP		0.99
MPC		0.75
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.82
gMVP		0.85
Mutation Taster		=6/94	disease causing (ClinVar)

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: rs28940308; hg19: chr22-18562674;