rs1554086368

Variant names:

• chr5-78955306-A-T
• rs1554086368
• NM_000046.5:c.887T>A

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1 PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000046.5(ARSB):​c.887T>A​(p.Ile296Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. I296L) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: ARSB NM_000046.5 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 8.83
• Publications: 0 publications found

Genes affected

ARSB (HGNC:714): (arylsulfatase B) Arylsulfatase B encoded by this gene belongs to the sulfatase family. The arylsulfatase B homodimer hydrolyzes sulfate groups of N-Acetyl-D-galactosamine, chondriotin sulfate, and dermatan sulfate. The protein is targeted to the lysozyme. Mucopolysaccharidosis type VI is an autosomal recessive lysosomal storage disorder resulting from a deficiency of arylsulfatase B. Two alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Dec 2016]

ARSB Gene-Disease associations (from GenCC):

• mucopolysaccharidosis type 6

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Genomics England PanelApp, Illumina, Labcorp Genetics (formerly Invitae), G2P, ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000046.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 85 curated pathogenic missense variants (we use a threshold of 10). The gene has 14 curated benign missense variants. Gene score misZ: 0.63089 (below the threshold of 3.09). Trascript score misZ: -0.06109 (below the threshold of 3.09). GenCC associations: The gene is linked to mucopolysaccharidosis type 6.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 5-78955306-A-T is Pathogenic according to our data. Variant chr5-78955306-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 559817.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ARSB	NM_000046.5	c.887T>A	p.Ile296Asn	missense_variant	Exon 4 of 8	ENST00000264914.10	NP_000037.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARSB	ENST00000264914.10	c.887T>A	p.Ile296Asn	missense_variant	Exon 4 of 8	1	NM_000046.5	ENSP00000264914.4
ARSB	ENST00000396151.7	c.887T>A	p.Ile296Asn	missense_variant	Exon 5 of 8	1		ENSP00000379455.3
ARSB	ENST00000565165.2	c.887T>A	p.Ile296Asn	missense_variant	Exon 4 of 5	1		ENSP00000456339.2
ARSB	ENST00000521800.2	n.69T>A		non_coding_transcript_exon_variant	Exon 1 of 3	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Mucopolysaccharidosis type 6 Pathogenic:2

Oct 28, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with asparagine, which is neutral and polar, at codon 296 of the ARSB protein (p.Ile296Asn). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with mucopolysaccharidosis type VI (PMID: 17458871). ClinVar contains an entry for this variant (Variation ID: 559817). 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 ARSB protein function with a positive predictive value of 95%. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Jan 01, 2018

Laboratory of Diagnosis and Therapy of Lysosomal Disorders, University of Padova

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

In vitro functional studies supportive of a damaging effect on the gene product (low to no ARSB activity in homozygotes; PS3); Absent from GnomAD (PM2) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.97	D;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Pathogenic	0.66	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.4	H;H;.
PhyloP100		8.8
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-6.5	D;D;D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;.;.
Vest4		0.90
MutPred		0.93		Gain of disorder (P = 0.0302);Gain of disorder (P = 0.0302);Gain of disorder (P = 0.0302);
MVP		1.0
MPC		1.2
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.99
gMVP		0.98
Mutation Taster		=6/94	disease causing (ClinVar)

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: rs1554086368; hg19: chr5-78251129;