22-18078378-T-G

Variant names:

• chr22-18078378-T-G
• rs74315506
• NM_001127649.3:c.2T>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PS1_Moderate PM2

The NM_001127649.3(PEX26):​c.2T>G​(p.Met1?) variant causes a start lost 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.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PEX26 NM_001127649.3 start_lost
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.58
• Publications: 7 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 12 ACMG points.

• PVS1: Start lost variant, next in-frame start position is after 22 pathogenic variants. Next in-frame start position is after 96 codons. Genomic position: 18079929. Lost 0.312 part of the original CDS.
• PS1: Another start lost variant in NM_001127649.3 (PEX26) was described as [Likely_pathogenic] in ClinVar
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PEX26	NM_001127649.3	c.2T>G	p.Met1?	start_lost	Exon 1 of 5	ENST00000399744.8	NP_001121121.1
PEX26	NM_017929.6	c.2T>G	p.Met1?	start_lost	Exon 2 of 6		NP_060399.1
PEX26	NM_001199319.2	c.2T>G	p.Met1?	start_lost	Exon 2 of 5		NP_001186248.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PEX26	ENST00000399744.8	c.2T>G	p.Met1?	start_lost	Exon 1 of 5	1	NM_001127649.3	ENSP00000382648.4
ENSG00000288683	ENST00000474897.6	n.2T>G		non_coding_transcript_exon_variant	Exon 2 of 9	5		ENSP00000434235.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000451 AC: 1 AN: 221904 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: 0.0000582

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Benign	0.19	.;T;T;.
Eigen	Uncertain	0.39
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Benign	0.46	N
LIST_S2	Uncertain	0.90	D;.;D;.
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.96	D;D;D;D
MetaSVM	Pathogenic	0.96	D
PhyloP100		1.6
PROVEAN	Uncertain	-2.7	.;D;D;D
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	.;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	.;D;D;.
Vest4		0.82
MutPred		0.69		Gain of MoRF binding (P = 0.0037);Gain of MoRF binding (P = 0.0037);Gain of MoRF binding (P = 0.0037);Gain of MoRF binding (P = 0.0037);
MVP		0.99
ClinPred		0.99	D
GERP RS		5.1
PromoterAI		0.044	Neutral
Varity_R		0.97
gMVP		0.73
Mutation Taster		=0/200	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: rs74315506; hg19: chr22-18561144;