chr22-18083639-C-T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001127649.3(PEX26):​c.574C>T​(p.Arg192*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,874 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 (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

PEX26
NM_001127649.3 stop_gained

Scores

2
3
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 1.59

Publications

7 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 22-18083639-C-T is Pathogenic according to our data. Variant chr22-18083639-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 928563.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
PEX26NM_001127649.3 linkc.574C>T p.Arg192* stop_gained Exon 3 of 5 ENST00000399744.8 NP_001121121.1 Q7Z412-1A0A024R100
PEX26NM_017929.6 linkc.574C>T p.Arg192* stop_gained Exon 4 of 6 NP_060399.1 Q7Z412-1A0A024R100
PEX26NM_001199319.2 linkc.574C>T p.Arg192* stop_gained Exon 4 of 5 NP_001186248.1 Q7Z412-2Q7Z2D7A0A0S2Z5M7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PEX26ENST00000399744.8 linkc.574C>T p.Arg192* stop_gained Exon 3 of 5 1 NM_001127649.3 ENSP00000382648.4 Q7Z412-1
PEX26ENST00000329627.11 linkc.574C>T p.Arg192* stop_gained Exon 4 of 6 1 ENSP00000331106.5 Q7Z412-1
PEX26ENST00000428061.2 linkc.574C>T p.Arg192* stop_gained Exon 3 of 4 1 ENSP00000412441.2 Q7Z412-2
ENSG00000288683ENST00000474897.6 linkn.574C>T non_coding_transcript_exon_variant Exon 4 of 9 5 ENSP00000434235.2 E9PRC5

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152074
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251294
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
22
AN:
1461800
Hom.:
0
Cov.:
32
AF XY:
0.0000165
AC XY:
12
AN XY:
727188
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.0000447
AC:
2
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000696
AC:
6
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5722
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1111994
Other (OTH)
AF:
0.00
AC:
0
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152074
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74284
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000242
AC:
1
AN:
41394
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68016
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 = 0.076386), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.392
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000360
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Peroxisome biogenesis disorder 7B;C3888385:Peroxisome biogenesis disorder 7A (Zellweger) Pathogenic:2
Aug 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg192*) in the PEX26 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PEX26 are known to be pathogenic (PMID: 12851857, 21031596). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individual(s) with peroxisome biogenesis disorders-Zellweger syndrome spectrum (PMID: 15542397). ClinVar contains an entry for this variant (Variation ID: 928563). For these reasons, this variant has been classified as Pathogenic. -

Mar 11, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:2
Oct 26, 2023
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 14, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 34804114, 25525159, 34426522, 12851857, 15542397, 19105186, 21031596) -

Peroxisome biogenesis disorder Pathogenic:2
May 17, 2023
Illumina Laboratory Services, Illumina
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The PEX26 c.574C>T (p.Arg192Ter) nonsense variant results in the loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. This variant has been reported with a second pathogenic PEX26 variant in an individual with clinical and laboratory features consistent with peroxisome biogenesis disorder (PMID: 15542397). This variant is not observed at a significant frequency in version 2.1.1 or version 3.1.2 of the Genome Aggregation Database and has been classified as pathogenic by at least three submitters in ClinVar. The c.574C>T variant was detected in a homozygous state. Based on the available evidence, the c.574C>T (p.Arg192Ter) variant is classified as pathogenic for peroxisome biogenesis disorder. -

May 06, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PEX26 c.574C>T (p.Arg192X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 2e-05 in 251294 control chromosomes (gnomAD). c.574C>T has been reported in the literature in individuals affected with Zellweger Syndrome (Ebberink_2010, Steinberg_2004). These data indicate that the variant may be associated with disease. A publication, Guder_2019, performed a functional study to assess the pathophysiological relevance of PEX26 oligomerization and found the variant of interest to not oligomerize but was still able to interact with PEX6. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as pathogenic. -

Peroxisome biogenesis disorder 7A (Zellweger) Pathogenic:1
Mar 07, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.55
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
35
DANN
Uncertain
1.0
Eigen
Uncertain
0.42
Eigen_PC
Benign
0.19
FATHMM_MKL
Uncertain
0.94
D
PhyloP100
1.6
Vest4
0.18
GERP RS
4.4
Mutation Taster
=2/198
disease causing (ClinVar)

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

Publications

Other links and lift over

dbSNP: rs61752136; hg19: chr22-18566405; API