3-25783328-G-T

Position:

• chr3-25783328-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_018297.4(NGLY1):​c.63C>A​(p.Cys21*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000416 in 1,442,126 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000042 (0 hom.)
• Consequence: NGLY1 NM_018297.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.357

Genes affected

NGLY1 (HGNC:17646): (N-glycanase 1) This gene encodes an enzyme that catalyzes hydrolysis of an N(4)-(acetyl-beta-D-glucosaminyl) asparagine residue to N-acetyl-beta-D-glucosaminylamine and a peptide containing an aspartate residue. The encoded enzyme may play a role in the proteasome-mediated degradation of misfolded glycoproteins. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Feb 2009]

OXSM (HGNC:26063): (3-oxoacyl-ACP synthase, mitochondrial) This gene encodes a beta-ketoacyl synthetase. The encoded enzyme is required for elongation of fatty acid chains in the mitochondria. Alternatively spliced transcript variants have been described.[provided by RefSeq, Feb 2009]

NGLY1 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-25783328-G-T is Pathogenic according to our data. Variant chr3-25783328-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 2895077.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NGLY1	NM_018297.4	c.63C>A	p.Cys21*	stop_gained	1/12	ENST00000280700.10	NP_060767.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NGLY1	ENST00000280700.10	c.63C>A	p.Cys21*	stop_gained	1/12	1	NM_018297.4	ENSP00000280700.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000416 AC: 6 AN: 1442126 Hom.: 0 Cov.: 34 AF XY: 0.00000279 AC XY: 2 AN XY: 715916

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000544

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital disorder of deglycosylation Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 13, 2023

This sequence change creates a premature translational stop signal (p.Cys21*) in the NGLY1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NGLY1 are known to be pathogenic (PMID: 24651605). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with NGLY1-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	0.71
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.78	D
Vest4		0.15
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs1182383020; hg19: chr3-25824819;