5-78781852-C-G

Variant names:

• chr5-78781852-C-G
• rs1554069772
• NM_000046.5:c.1336G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000046.5(ARSB):​c.1336G>C​(p.Gly446Arg) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 15/26 in silico tools predict a damaging outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G446S) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ARSB NM_000046.5 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.59
• Publications: 1 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 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: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ARSB	NM_000046.5	c.1336G>C	p.Gly446Arg	missense_variant, splice_region_variant	Exon 7 of 8	ENST00000264914.10	NP_000037.2
ARSB	XM_011543390.2	c.1336G>C	p.Gly446Arg	missense_variant, splice_region_variant	Exon 8 of 9		XP_011541692.1
ARSB	XR_001742066.3	n.*61G>C		downstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARSB	ENST00000264914.10	c.1336G>C	p.Gly446Arg	missense_variant, splice_region_variant	Exon 7 of 8	1	NM_000046.5	ENSP00000264914.4
ARSB	ENST00000521011.1	n.301G>C		splice_region_variant, non_coding_transcript_exon_variant	Exon 2 of 3	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Mucopolysaccharidosis type 6 Uncertain:1

Jan 01, 2018

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

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

Absent from GnomAD (PM2); Multiple lines of computational evidence support a deleterious effect on the gene product (PP3) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	35
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.77	D
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.63	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M
PhyloP100		6.6
PrimateAI	Uncertain	0.58	T
PROVEAN	Pathogenic	-6.0	D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.028	D
Sift4G	Uncertain	0.030	D
Polyphen		1.0	D
Vest4		0.89
MutPred		0.87		Gain of MoRF binding (P = 0.0126);
MVP		0.99
MPC		0.95
ClinPred		0.98	D
GERP RS		5.5
Varity_R		0.89
gMVP		0.88
Mutation Taster		=4/96	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.98		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1554069772; hg19: chr5-78077675;