NM_000203.5:c.1728-1G>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1PM3PM2_SupportingPP4

This summary comes from the ClinGen Evidence Repository: The NM_000203.5:c.1728-1G>C variant in IDUA occurs within the canonical splice acceptor site of intron 12. It is predicted to cause skipping of biologically-relevant exon 13 out of 14, resulting in a frameshift leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1). At least 3 patients with this variant had documented IDUA deficiency within the affected range and urinary GAG elevation above normal range (PP4; PMID:31194252). This variant has been detected in at least 2 individuals with MPS I. Of those individuals, both were compound heterozygous for the variant and a pathogenic variant (Q70X; W402X) and neither of those were confirmed in trans (PM3; PMID:31194252). The highest population minor allele frequency in gnomAD v4.0. is 0.00001612 (19/1178792 alleles) in the European (non-Finnish) population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.00025), meeting this criterion (PM2_Supporting). In summary, this variant meets the criteria to be classified as pathogenic for MPS I based on the IDUA-specific ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert panel (Specifications Version 1.0): PVS1, PP4, PM3, PM2_Supporting.(Classification approved by the ClinGen Lysosomal Diseases Variant Curation Expert Panel on December 5, 2024) LINK:https://erepo.genome.network/evrepo/ui/classification/CA355965306/MONDO:0001586/091

Frequency

Genomes: 𝑓 0.0000067 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

IDUA
NM_000203.5 splice_acceptor, intron

Scores

5
1
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic reviewed by expert panel P:5O:1

Conservation

PhyloP100: 1.84

Publications

0 publications found
Variant links:
Genes affected
IDUA (HGNC:5391): (alpha-L-iduronidase) This gene encodes an enzyme that hydrolyzes the terminal alpha-L-iduronic acid residues of two glycosaminoglycans, dermatan sulfate and heparan sulfate. This hydrolysis is required for the lysosomal degradation of these glycosaminoglycans. Mutations in this gene that result in enzymatic deficiency lead to the autosomal recessive disease mucopolysaccharidosis type I (MPS I). [provided by RefSeq, Jul 2008]
IDUA Gene-Disease associations (from GenCC):
  • mucopolysaccharidosis type 1
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Myriad Women’s Health
  • Scheie syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), Orphanet
  • Hurler syndrome
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, PanelApp Australia
  • Hurler-Scheie syndrome
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
For more information check the summary or visit ClinGen Evidence Repository.
PM2
For more information check the summary or visit ClinGen Evidence Repository.
PM3
For more information check the summary or visit ClinGen Evidence Repository.
PP4
For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IDUANM_000203.5 linkc.1728-1G>C splice_acceptor_variant, intron_variant Intron 12 of 13 ENST00000514224.2 NP_000194.2 P35475-1
IDUANM_001363576.1 linkc.1332-1G>C splice_acceptor_variant, intron_variant Intron 11 of 12 NP_001350505.1
IDUANR_110313.1 linkn.1820-1G>C splice_acceptor_variant, intron_variant Intron 12 of 13
IDUAXM_047415650.1 linkc.*20-1G>C splice_acceptor_variant, intron_variant Intron 11 of 11 XP_047271606.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IDUAENST00000514224.2 linkc.1728-1G>C splice_acceptor_variant, intron_variant Intron 12 of 13 2 NM_000203.5 ENSP00000425081.2 P35475-1
IDUAENST00000247933.9 linkc.1728-1G>C splice_acceptor_variant, intron_variant Intron 12 of 13 1 ENSP00000247933.4 P35475-1
IDUAENST00000514698.5 linkn.1839-1G>C splice_acceptor_variant, intron_variant Intron 9 of 10 5
IDUAENST00000652070.1 linkn.1784-1G>C splice_acceptor_variant, intron_variant Intron 11 of 12

Frequencies

GnomAD3 genomes
AF:
0.00000666
AC:
1
AN:
150260
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000245
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251038
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1460418
Hom.:
0
Cov.:
31
AF XY:
0.00000963
AC XY:
7
AN XY:
726586
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33458
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86240
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52800
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000171
AC:
19
AN:
1111248
Other (OTH)
AF:
0.00
AC:
0
AN:
60360
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000666
AC:
1
AN:
150260
Hom.:
0
Cov.:
32
AF XY:
0.0000137
AC XY:
1
AN XY:
73166
show subpopulations
African (AFR)
AF:
0.0000245
AC:
1
AN:
40758
American (AMR)
AF:
0.00
AC:
0
AN:
15018
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3460
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5132
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4670
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67544
Other (OTH)
AF:
0.00
AC:
0
AN:
2046
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.675
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5Other:1
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Mucopolysaccharidosis type 1 Pathogenic:3Other:1
-
GenomeConnect, ClinGen
Significance:not provided
Review Status:no classification provided
Collection Method:phenotyping only

Variant interpretted as Pathogenic and reported on 07-30-2019 by Lab or GTR ID 26957. GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -

Apr 05, 2021
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Dec 05, 2024
ClinGen Lysosomal Storage Disorder Variant Curation Expert Panel
Significance:Pathogenic
Review Status:reviewed by expert panel
Collection Method:curation

The NM_000203.5:c.1728-1G>C variant in IDUA occurs within the canonical splice acceptor site of intron 12. It is predicted to cause skipping of biologically-relevant exon 13 out of 14, resulting in a frameshift leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1). At least 3 patients with this variant had documented IDUA deficiency within the affected range and urinary GAG elevation above normal range (PP4; PMID: 31194252). This variant has been detected in at least 2 individuals with MPS I. Of those individuals, both were compound heterozygous for the variant and a pathogenic variant (Q70X; W402X) and neither of those were confirmed in trans (PM3; PMID: 31194252). The highest population minor allele frequency in gnomAD v4.0. is 0.00001612 (19/1178792 alleles) in the European (non-Finnish) population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.00025), meeting this criterion (PM2_Supporting). In summary, this variant meets the criteria to be classified as pathogenic for MPS I based on the IDUA-specific ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert panel (Specifications Version 1.0): PVS1, PP4, PM3, PM2_Supporting. (Classification approved by the ClinGen Lysosomal Diseases Variant Curation Expert Panel on December 5, 2024) -

Oct 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change affects an acceptor splice site in intron 12 of the IDUA gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in IDUA are known to be pathogenic (PMID: 11735025, 21480867). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individuals with mucopolysaccharidosis type I (PMID: 22976768, 28752568). ClinVar contains an entry for this variant (Variation ID: 556064). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Mucopolysaccharidosis, MPS-I-H/S Pathogenic:1
Nov 18, 2021
Myriad Genetics, Inc.
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

NM_000203.3(IDUA):c.1728-1G>C is a a canonical splice variant classified as likely pathogenic in the context of mucopolysaccharidosis type I. c.1728-1G>C has been observed in cases with relevant disease (PMID: 31194252). Functional assessments of this variant are not available in the literature. c.1728-1G>C has not been observed in population frequency databases. In summary, NM_000203.3(IDUA):c.1728-1G>C is a canonical splice variant that has been observed more frequently in cases with the relevant disease than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -

not provided Pathogenic:1
Dec 15, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Canonical splice site variant in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 28752568, 22976768) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.22
CADD
Pathogenic
35
DANN
Uncertain
0.99
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.90
FATHMM_MKL
Pathogenic
0.98
D
PhyloP100
1.8
GERP RS
4.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=2/98
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
0.74
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.74
Position offset: -25
DS_AL_spliceai
0.61
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs1249951282; hg19: chr4-997799; API