rs752131463

Positions:

• chr17-42541069-TC-T

Variant summary

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

The NM_000263.4(NAGLU):​c.886del​(p.Leu296CysfsTer4) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,894 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: NAGLU NM_000263.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.47

Genes affected

NAGLU (HGNC:7632): (N-acetyl-alpha-glucosaminidase) This gene encodes an enzyme that degrades heparan sulfate by hydrolysis of terminal N-acetyl-D-glucosamine residues in N-acetyl-alpha-D-glucosaminides. Defects in this gene are the cause of mucopolysaccharidosis type IIIB (MPS-IIIB), also known as Sanfilippo syndrome B. This disease is characterized by the lysosomal accumulation and urinary excretion of heparan sulfate. [provided by RefSeq, Jul 2008]

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 17-42541069-TC-T is Pathogenic according to our data. Variant chr17-42541069-TC-T is described in ClinVar as [Pathogenic]. Clinvar id is 521841.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NAGLU	NM_000263.4	c.886del	p.Leu296CysfsTer4	frameshift_variant	5/6	ENST00000225927.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NAGLU	ENST00000225927.7	c.886del	p.Leu296CysfsTer4	frameshift_variant	5/6	1	NM_000263.4	P1
NAGLU	ENST00000586516.5	c.488del	p.Leu164CysfsTer4	frameshift_variant	4/4	2
NAGLU	ENST00000591587.1	c.360-1957del		intron_variant		5
NAGLU	ENST00000592454.1			upstream_gene_variant		2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251494 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135922

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

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: 0.00000205 AC: 3 AN: 1461894 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727248

Gnomad4 AFR exome AF: 0.0000597

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 20, 2017

- -

Mucopolysaccharidosis, MPS-III-B;C5569050:Charcot-Marie-Tooth disease axonal type 2V Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Aug 16, 2023

This variant is present in population databases (rs752131463, gnomAD 0.007%). This sequence change creates a premature translational stop signal (p.Leu296Cysfs*4) in the NAGLU gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NAGLU are known to be pathogenic (PMID: 9832037, 10094189, 16151907). This variant has not been reported in the literature in individuals affected with NAGLU-related conditions. ClinVar contains an entry for this variant (Variation ID: 521841). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		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: rs752131463; hg19: chr17-40693087;