rs772994617

Positions:

• chr3-25739587-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_018297.4(NGLY1):​c.871C>T​(p.Arg291Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,698 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: NGLY1 NM_018297.4 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.50

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]

ACMG classification

Verdict is Pathogenic. Variant got 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 3-25739587-G-A is Pathogenic according to our data. Variant chr3-25739587-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 474235.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NGLY1	NM_018297.4	c.871C>T	p.Arg291Ter	stop_gained	5/12	ENST00000280700.10	NP_060767.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NGLY1	ENST00000280700.10	c.871C>T	p.Arg291Ter	stop_gained	5/12	1	NM_018297.4	ENSP00000280700	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250882 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135572

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461698 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727154

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Congenital disorder of deglycosylation Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 03, 2023

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 474235). This variant has not been reported in the literature in individuals affected with NGLY1-related conditions. This variant is present in population databases (rs772994617, gnomAD 0.006%). This sequence change creates a premature translational stop signal (p.Arg291*) 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). -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Mar 22, 2019

A variant that is likely pathogenic has been identified in the NGLY1 gene. The R291X variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The R291X variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). The R291X nonsense variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.62
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Pathogenic	0.98	D
MutationTaster	Benign	1.0	A;A;A;A;D
Vest4		0.46
GERP RS		3.8

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs772994617; hg19: chr3-25781078; COSMIC: COSV54984261; COSMIC: COSV54984261;