rs398123249

Positions:

• chrX-149503468-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000202.8(IDS):​c.262C>T​(p.Arg88Cys) variant causes a missense change. 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R88H) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 23)
• Consequence: IDS NM_000202.8 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:9
• Conservation: PhyloP100: 3.74

Genes affected

IDS (HGNC:5389): (iduronate 2-sulfatase) This gene encodes a member of the sulfatase family of proteins. The encoded preproprotein is proteolytically processed to generate two polypeptide chains. This enzyme is involved in the lysosomal degradation of heparan sulfate and dermatan sulfate. Mutations in this gene are associated with the X-linked lysosomal storage disease mucopolysaccharidosis type II, also known as Hunter syndrome. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed. [provided by RefSeq, Jan 2016]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000202.8
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-149503467-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 950955.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996
• PP5: Variant X-149503468-G-A is Pathogenic according to our data. Variant chrX-149503468-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 92618.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-149503468-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
IDS	NM_000202.8	c.262C>T	p.Arg88Cys	missense_variant	3/9	ENST00000340855.11
IDS	NM_006123.5	c.262C>T	p.Arg88Cys	missense_variant	3/8
IDS	NM_001166550.4	c.15-23C>T		intron_variant
IDS	NR_104128.2	n.431C>T		non_coding_transcript_exon_variant	3/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
IDS	ENST00000340855.11	c.262C>T	p.Arg88Cys	missense_variant	3/9	1	NM_000202.8	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 25

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Mucopolysaccharidosis, MPS-II Pathogenic:8

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jul 26, 2017	A different missense substitution at this codon (p.Arg88His) has been determined to be pathogenic (PMID: 9921913, 9660053, 10215411, 10838181, 24515576). This suggests that the arginine residue is critical for IDS protein function and that other missense substitutions at this position may also be pathogenic. For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects IDS post-translational modification and results in a protein with an almost undetectable enzymatic activity (PMID: 15614569, 22990955). This variant has been reported in several individuals affected with mucopolysaccharidosis type II (PMID: 7814022, 8940265 , 9950361 , 15614569, 17063374, 22990955, 24125893, 26762690). ClinVar contains an entry for this variant (Variation ID: 92618). While this variant is not present in population databases, the frequency information is unreliable, as metrics indicate poor data quality at this position in the ExAC database. This sequence change replaces arginine with cysteine at codon 88 of the IDS protein (p.Arg88Cys). The arginine residue is highly conserved and there is a large physicochemical difference between arginine and cysteine. -
Pathogenic, criteria provided, single submitter	clinical testing	Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences	-	- -
Pathogenic, criteria provided, single submitter	literature only	Laboratory of Diagnosis and Therapy of Lysosomal Disorders, University of Padova	Jun 07, 2024	In vitro or in vivo functional studies supportive of a damaging effect (PS3_Strong), Prevalence of the variant significantly increased in affected individuals compared with controls (PS4_Strong), Located in a mutational hot spot and/or critical functional domain (PM1_Moderate), Absent from controls (or at low frequency) in gnomAD database (PM2_Moderate), Cosegregation with disease in multiple affected family members (PP1_Moderate), Missense variant in a gene with a low rate of benign missense variation (PP2_Supporting), Multiple lines of computational evidence support a deleterious effect (PP3_Supporting), Patient’s phenotype or family history highly specific for the disease (PP4_Strong) -
Pathogenic, criteria provided, single submitter	clinical testing	Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics	Sep 01, 2022	The hemizygous status for variant c.262C>T(p.Arg88Cys) in exon 3 of IDS gene. The variant has not been repoted in the 1000 genome gnomAD databases. The in silico prediction is damaging by DANN, LRT, SIFT and MutationTaster. -
Pathogenic, criteria provided, single submitter	clinical testing	Kasturba Medical College, Manipal, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Sep 05, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Feb 23, 2022	Variant summary: IDS c.262C>T (p.Arg88Cys) results in a non-conservative amino acid change located in the Sulfatase, N-terminal domain (IPR000917) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 114316 control chromosomes (gnomAD). c.262C>T has been reported in the literature in multiple individuals affected with Mucopolysaccharidosis Type II (Hunter Syndrome) (e.g. Parkinson_2004, Chang_2005, Froissart_2007, Charoenwattanasatien_2012, Dvorakova_2017). These data indicate that the variant is very likely to be associated with disease. Experimental evidence demonstrated the variant confers very little residual IDS activity (Chang_2005, Charoenwattanasatien_2012). Two ClinVar submitters (evaluation after 2014) cite the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jun 30, 2022	- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Jan 09, 2013

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.69	D
BayesDel_noAF	Pathogenic	0.76
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D;.;D
FATHMM_MKL	Uncertain	0.76	D
LIST_S2	Pathogenic	1.0	D;D;D
M_CAP	Pathogenic	0.90	D
MetaRNN	Pathogenic	1.0	D;D;D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	5.0	H;H;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-7.4	D;D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;D
Vest4		0.89
MutPred		0.98		Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);
MVP		1.0
MPC		2.6
ClinPred		1.0	D
GERP RS		2.3
Varity_R		0.99
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.17		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: rs398123249; hg19: chrX-148584998;