rs1557340280

Positions:

• chrX-149503473-G-A
• chrX-149503473-G-C

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PM2 PM5 PP3 PP5_Very_Strong

The NM_000202.8(IDS):​c.257C>T​(p.Pro86Leu) 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P86Q) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 22)
• Consequence: IDS NM_000202.8 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 9.42

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 13 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant X-149503473-G-A is Pathogenic according to our data. Variant chrX-149503473-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 527322.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-149503473-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IDS	NM_000202.8	c.257C>T	p.Pro86Leu	missense_variant	3/9	ENST00000340855.11	NP_000193.1
IDS	NM_006123.5	c.257C>T	p.Pro86Leu	missense_variant	3/8		NP_006114.1
IDS	NM_001166550.4	c.15-28C>T		intron_variant			NP_001160022.1
IDS	NR_104128.2	n.426C>T		non_coding_transcript_exon_variant	3/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IDS	ENST00000340855.11	c.257C>T	p.Pro86Leu	missense_variant	3/9	1	NM_000202.8	ENSP00000339801	P1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 24

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Mucopolysaccharidosis, MPS-II Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jun 29, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jun 15, 2022	For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. Experimental studies have shown that this missense change affects IDS function (PMID: 9573369, 26407519). 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 IDS protein function. ClinVar contains an entry for this variant (Variation ID: 527322). This missense change has been observed in individual(s) with mucopolysaccharidosis (MPS) type II (PMID: 7728156, 9573369, 10215411, 17063374, 22976768, 24515576, 28077157). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 86 of the IDS protein (p.Pro86Leu). -
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), 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_Moderate) -

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 05, 2018

The p.P86L pathogenic mutation (also known as c.257C>T), located in coding exon 3 of the IDS gene, results from a C to T substitution at nucleotide position 257. The proline at codon 86 is replaced by leucine, an amino acid with a few similar properties. This mutation has been detected in several individuals with Mucopolysaccharidosis type II (MPS II; also called Hunter syndrome) (Popowska E, et al. Hum. Mutat. 1995;5(1):97-100; Vafiadaki E, et al. Arch. Dis. Child. 1998 79(3):237-41; Isogai K, et al. J. Inherit. Metab. Dis. 1998;21(1):60-70; Lampe C et al. JIMD Rep, 2014 Mar;14:99-113; Kosuga M et al. Mol. Genet. Metab., 2016 07;118:190-7), and occurred de novo in at least one individual (Chiong MA et al. Orphanet J Rare Dis, 2017 01;12:7). In addition, several functional studies have shown that this mutation disrupts splicing, resulting in a truncated mRNA product which causes a decrease in IDS enzymatic activity and lysosomal formation (Isogai K, et al. J. Inherit. Metab. Dis. 1998;21(1):60-70; Sukegawa-Hayasaka K, et al. J. Inherit. Metab. Dis. 2006 Dec; 29(6):755-61; Matos L et al. Biochim. Biophys. Acta, 2015 Dec;1852:2712-21; Millat G et al. Biochim. Biophys. Acta, 1998 Mar;1406:214-8). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Jun 01, 2024

IDS: PM1, PM2, PM5, PM6, PS4:Moderate, PP3, PS3:Supporting -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.82
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;.;D;.
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Pathogenic	0.94	D
MetaRNN	Pathogenic	1.0	D;D;D;D
MetaSVM	Pathogenic	0.89	D
MutationAssessor	Pathogenic	5.0	H;H;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-9.2	D;D;D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;.
Polyphen		1.0	D;D;D;.
Vest4		0.89
MutPred		0.98		Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);
MVP		1.0
MPC		2.2
ClinPred		1.0	D
GERP RS		4.4
Varity_R		0.98
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.62		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.62		Position offset: -28

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

Publications

LitVar

Other links and lift over

dbSNP: rs1557340280; hg19: chrX-148585003;