17-42537475-T-G

Variant names:

• chr17-42537475-T-G
• rs770684838
• NM_000263.4:c.461T>G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000263.4(NAGLU):​c.461T>G​(p.Ile154Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,878 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. I154T) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 35)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: NAGLU NM_000263.4 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2 U:1
• Conservation: PhyloP100: 7.63
• Publications: 1 publications found

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 Gene-Disease associations (from GenCC):

• mucopolysaccharidosis type 3B

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, Orphanet, G2P, Myriad Women’s Health
• Charcot-Marie-Tooth disease axonal type 2V

  Inheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet

ENSG00000266929 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain 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 chr17-42537475-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2503909.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 17-42537475-T-G is Pathogenic according to our data. Variant chr17-42537475-T-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 558352.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000263.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NAGLU	NM_000263.4	MANE Select	c.461T>G	p.Ile154Arg	missense	Exon 2 of 6	NP_000254.2	A0A140VJE4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NAGLU	ENST00000225927.7	TSL:1 MANE Select	c.461T>G	p.Ile154Arg	missense	Exon 2 of 6	ENSP00000225927.1	P54802
	NAGLU	ENST00000963429.1		c.539T>G	p.Ile180Arg	missense	Exon 2 of 6	ENSP00000633488.1
	NAGLU	ENST00000904921.1		c.518T>G	p.Ile173Arg	missense	Exon 3 of 7	ENSP00000574980.1

Frequencies

GnomAD3 genomes Cov.: 35

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251392 AF XY: 0.00000736

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 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: 1461878 Hom.: 0 Cov.: 58 AF XY: 0.00000275 AC XY: 2 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112008

Other (OTH) AF: 0.0000166 AC: 1 AN: 60394

GnomAD4 genome Cov.: 35

Alfa AF: 0.0000719 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	1	-	Mucopolysaccharidosis, MPS-III-B (2)
1	-	-	Mucopolysaccharidosis, MPS-III-B;C5569050:Charcot-Marie-Tooth disease axonal type 2V (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.84
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.99	D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		7.6
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-6.5	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.99	D
Vest4		0.85
MutPred		0.93		Loss of stability (P = 0.0539)
MVP		1.0
MPC		1.6
ClinPred		1.0	D
GERP RS		4.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.99
gMVP		0.99
Mutation Taster		=11/89	disease causing

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

Other links and lift over

dbSNP: rs770684838; hg19: chr17-40689493;