chr22-18078604-C-A

Variant names:

• chr22-18078604-C-A
• rs786205556
• NM_001127649.3:c.228C>A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_001127649.3(PEX26):​c.228C>A​(p.Gly76Gly) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000691 in 1,446,322 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G76G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: PEX26 NM_001127649.3 splice_region, synonymous
• Scores: Splicing: ADA: 0.001654
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.67
• Publications: 0 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: G2P, Labcorp Genetics (formerly Invitae)
• peroxisome biogenesis disorder 7B

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000288683 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.42).
• BP7: Synonymous conserved (PhyloP=2.67 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001127649.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PEX26	NM_001127649.3	MANE Select	c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 1 of 5	NP_001121121.1	Q7Z412-1
	PEX26	NM_017929.6		c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 2 of 6	NP_060399.1	Q7Z412-1
	PEX26	NM_001199319.2		c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 2 of 5	NP_001186248.1	Q7Z412-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PEX26	ENST00000399744.8	TSL:1 MANE Select	c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 1 of 5	ENSP00000382648.4	Q7Z412-1
	PEX26	ENST00000329627.11	TSL:1	c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 2 of 6	ENSP00000331106.5	Q7Z412-1
	PEX26	ENST00000428061.2	TSL:1	c.228C>A	p.Gly76Gly	splice_region synonymous	Exon 1 of 4	ENSP00000412441.2	Q7Z412-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.91e-7 AC: 1 AN: 1446322 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 718834

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

African (AFR) AF: 0.00 AC: 0 AN: 33226

American (AMR) AF: 0.0000230 AC: 1 AN: 43448

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25884

East Asian (EAS) AF: 0.00 AC: 0 AN: 39108

South Asian (SAS) AF: 0.00 AC: 0 AN: 84338

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 47318

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1107366

Other (OTH) AF: 0.00 AC: 0 AN: 59884

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.42
CADD	Benign	17
DANN	Benign	0.91
PhyloP100		2.7
PromoterAI		-0.051	Neutral

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0017
dbscSNV1_RF	Benign	0.10
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: rs786205556; hg19: chr22-18561370;