chr8-76980367-A-G

Position:

• chr8-76980367-A-G

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_000318.3(PEX2):​c.*2894T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00255 in 152,340 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0026 (1 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PEX2 NM_000318.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.138

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]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00255 (389/152340) while in subpopulation NFE AF= 0.00442 (301/68024). AF 95% confidence interval is 0.00401. There are 1 homozygotes in gnomad4. There are 194 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PEX2	NM_000318.3	c.*2894T>C		3_prime_UTR_variant	4/4	ENST00000357039.9
PEX2	NM_001079867.2	c.*2894T>C		3_prime_UTR_variant	3/3
PEX2	NM_001172086.2	c.*2894T>C		3_prime_UTR_variant	5/5
PEX2	NM_001172087.2	c.*2894T>C		3_prime_UTR_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PEX2	ENST00000357039.9	c.*2894T>C		3_prime_UTR_variant	4/4	1	NM_000318.3	P1

Frequencies

GnomAD3 genomes AF: 0.00256 AC: 389 AN: 152222 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.000724

Gnomad AMI AF: 0.00110

Gnomad AMR AF: 0.00170

Gnomad ASJ AF: 0.000576

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00331

Gnomad FIN AF: 0.000565

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00442

Gnomad OTH AF: 0.00335

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 4 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 4

Gnomad4 NFE exome AF: 0.00

GnomAD4 genome AF: 0.00255 AC: 389 AN: 152340 Hom.: 1 Cov.: 32 AF XY: 0.00260 AC XY: 194 AN XY: 74504

Gnomad4 AFR AF: 0.000722

Gnomad4 AMR AF: 0.00170

Gnomad4 ASJ AF: 0.000576

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00331

Gnomad4 FIN AF: 0.000565

Gnomad4 NFE AF: 0.00442

Gnomad4 OTH AF: 0.00331

Alfa AF: 0.00323 Hom.: 1

Bravo AF: 0.00251

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Peroxisome biogenesis disorder 5A (Zellweger) Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	5.5
DANN	Benign	0.86

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

Publications

LitVar

Other links and lift over

dbSNP: rs569387185; hg19: chr8-77892603;