rs763299645

Positions:

chr17-42544026-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000263.4(NAGLU):c.2020C>T(p.Arg674Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000168 in 1,611,266 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R674H) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

NAGLU
NM_000263.4 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 5.84

Variant links:

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]

NAGLU links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1

In a helix (size 16) in uniprot entity ANAG_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_000263.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr17-42544027-G-A is described in Lovd as [Pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.995

PP5

Variant 17-42544026-C-T is Pathogenic according to our data. Variant chr17-42544026-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 553061.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
NAGLU	NM_000263.4 linkuse as main transcript	c.2020C>T	p.Arg674Cys	missense_variant	6/6	ENST00000225927.7	NP_000254.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NAGLU	ENST00000225927.7 linkuse as main transcript	c.2020C>T	p.Arg674Cys	missense_variant	6/6	1	NM_000263.4	ENSP00000225927	P1
NAGLU	ENST00000591587.1 linkuse as main transcript	c.*989C>T		3_prime_UTR_variant	4/4	5		ENSP00000467836

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152150

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000163

AC:

AN:

244800

Hom.:

AF XY:

0.00000754

AC XY:

AN XY:

132548

show subpopulations

Gnomad AFR exome

AF:

0.0000650

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000334

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000181

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000164

AC:

AN:

1459116

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

725588

show subpopulations

Gnomad4 AFR exome

AF:

0.0000897

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000350

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000162

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152150

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74330

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000324

Hom.:

Bravo

AF:

0.0000302

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-III-B

Pathogenic:4

Likely pathogenic, criteria provided, single submitter	clinical testing	Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics	-	The homozygous missense variation in exon 6 of NAGLU gene that results in the amino acid substitution to cysteine for arginine at codon of 674 was detected. The variant c.2020C>T (p.Arg674Cys) has not been reported in 1000 genome and has a MAF of 0.0016% in the gnomAD database. The insilico prediction of the variant is dIsease causing by MutationTaster , LRT, SIFT, PROVEAN and DANN. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jul 27, 2017	- -
Pathogenic, no assertion criteria provided	research	Molecular Biology Laboratory, Department of Zoology, Quaid-i-azam University	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 14, 2021	- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

Dec 20, 2021

- -

Tip-toe gait

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Practice for Gait Abnormalities, David Pomarino, Competency Network Toe Walking c/o Practice Pomarino

Nov 30, 2021

Hereditary motor sensory neuropathy (HMSN), also known as Charcot-Marie-Tooth Disease (CMT), is the most commonly inherited peripheral polyneuropathy. It constitutes a group of inherited, progressive, motor and sensory peripheral nerve disorders with properties of demyelination, axonal degeneration, or both. It is classified by clinical characteristics, modes of inheritance, electrophysiologic features, metabolic defects, and specific gene markers. Our patients all walk on tiptoe, so they show similar symptoms. When we genetically test them with our toe walking panel, we find that around 90 per cent of them have a genetic variant that explains their toe walking. These can be assigned, for example, to the area of myopathies (such as variants of the COL6A3 gene), the area of hereditary neuropathies (such as variants of the KMT2C gene) or the area of metabolic diseases (such as variants of the PYGM gene). In a smaller group of patients with almost identical symptoms, no abnormality is found in the genes of our panel, but spastic paraplegia can be detected. In another small group of our toe walkers, no abnormalities can be detected in the genes analysed in our toe walking panel, nor do they suffer from spastic paraplegia, as is also the case with healthy children. In contrast to these, however, they show a tiptoe gait. These patients suffer from infantile cerebral palsy, in which toe walking can also be observed. -

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

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 01, 2024

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 674 of the NAGLU protein (p.Arg674Cys). This variant is present in population databases (rs763299645, gnomAD 0.007%). This missense change has been observed in individual(s) with mucopolysaccharidosis type IIIB (PMID: 9443875, 10094189). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 553061). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt NAGLU protein function with a positive predictive value of 95%. This variant disrupts the p.Arg674 amino acid residue in NAGLU. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 8650226, 9443875, 9950362, 20852935). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.69

BayesDel_addAF

Pathogenic

0.44

BayesDel_noAF

Pathogenic

0.57

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.99

Eigen

Pathogenic

0.75

Eigen_PC

Uncertain

0.61

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.91

M_CAP

Pathogenic

0.78

MetaRNN

Pathogenic

1.0

MetaSVM

Pathogenic

0.91

MutationAssessor

Pathogenic

3.7

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.62

PROVEAN

Pathogenic

-7.6

REVEL

Pathogenic

0.96

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.99

MutPred

0.97

Gain of catalytic residue at W675 (P = 0.0011);

MVP

1.0

MPC

1.4

ClinPred

1.0

GERP RS

4.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.96

gMVP

0.94

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over