4-1002325-C-G

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PP4PM2_SupportingPM3_StrongPVS1

This summary comes from the ClinGen Evidence Repository: The NM_000203.5(IDUA):c.1029C>G (p.Tyr343Ter) variant is a nonsense variant observed to cause a premature stop codon in biologically relevant exon 8 (out of 14), leading to nonsense-mediated decay in the IDUA gene in which loss-of-function is an established disease mechanism. Expression of the variant in COS-7 cells showed 1.1% of normal IDUA activity (PMID:9391892) (PVS1). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00006 (1/15956 alleles) in the African population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.0025), meeting this criterion (PM2_Supporting). This variant has been detected in at least 3 individuals with MPS I. Of those individuals, 2 were heterozygous for the variant and a pathogenic or likely pathogenic variant (variants are: c.208C>T (p.Gln70Ter), c.3G>A (p.Met1?)), and one of those was confirmed in trans (PMIDs: 15081804, 9391892, 8019572) (PM3_Strong). At least 1 patient with this variant had undetectable IDUA activity in skin fibroblasts (PP4) (PMID:15081804). There is a ClinVar entry for this variant (Variation ID: 550474). In summary, this variant meets the criteria to be classified as pathogenic for MPS I based on the ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert Panel (Specifications Version 1.0.0): PVS1, PM2_Supporting, PM3_Strong, PP4.(Classification approved by the ClinGen Lysosomal Diseases Variant Curation Expert Panel on December 5, 2024) LINK:https://erepo.genome.network/evrepo/ui/classification/CA2802166/MONDO:0001586/010

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)

Consequence

IDUA
NM_000203.5 stop_gained

Scores

1
6

Clinical Significance

Pathogenic reviewed by expert panel P:6

Conservation

PhyloP100: -0.0490

Publications

9 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 14 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.1029C>G p.Tyr343* stop_gained Exon 8 of 14 ENST00000514224.2 NP_000194.2
IDUANM_001363576.1 linkc.633C>G p.Tyr211* stop_gained Exon 7 of 13 NP_001350505.1
IDUAXM_047415650.1 linkc.1029C>G p.Tyr343* stop_gained Exon 8 of 12 XP_047271606.1
IDUANR_110313.1 linkn.1117C>G non_coding_transcript_exon_variant Exon 8 of 14

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IDUAENST00000514224.2 linkc.1029C>G p.Tyr343* stop_gained Exon 8 of 14 2 NM_000203.5 ENSP00000425081.2
IDUAENST00000247933.9 linkc.1029C>G p.Tyr343* stop_gained Exon 8 of 14 1 ENSP00000247933.4
IDUAENST00000514698.5 linkn.1136C>G non_coding_transcript_exon_variant Exon 5 of 11 5
IDUAENST00000652070.1 linkn.1085C>G non_coding_transcript_exon_variant Exon 7 of 13

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152270
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000403
AC:
1
AN:
248154
AF XY:
0.00000742
show subpopulations
Gnomad AFR exome
AF:
0.0000627
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Cov.:
35
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152270
Hom.:
0
Cov.:
34
AF XY:
0.0000269
AC XY:
2
AN XY:
74398
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41478
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.00000827
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:6
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Mucopolysaccharidosis type 1 Pathogenic:3
Nov 02, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Tyr343*) in the IDUA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in IDUA are known to be pathogenic (PMID: 11735025, 21480867). This variant is present in population databases (rs764196171, gnomAD 0.007%). This premature translational stop signal has been observed in individual(s) with mucopolysaccharidosis type I (PMID: 8019572, 9391892, 31298590). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 550474). 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. -

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(IDUA):c.1029C>G (p.Tyr343Ter) variant is a nonsense variant observed to cause a premature stop codon in biologically relevant exon 8 (out of 14), leading to nonsense-mediated decay in the IDUA gene in which loss-of-function is an established disease mechanism. Expression of the variant in COS-7 cells showed 1.1% of normal IDUA activity (PMID: 9391892) (PVS1). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00006 (1/15956 alleles) in the African population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.0025), meeting this criterion (PM2_Supporting). This variant has been detected in at least 3 individuals with MPS I. Of those individuals, 2 were heterozygous for the variant and a pathogenic or likely pathogenic variant (variants are: c.208C>T (p.Gln70Ter), c.3G>A (p.Met1?)), and one of those was confirmed in trans (PMIDs: 15081804, 9391892, 8019572) (PM3_Strong). At least 1 patient with this variant had undetectable IDUA activity in skin fibroblasts (PP4) (PMID: 15081804). There is a ClinVar entry for this variant (Variation ID: 550474). In summary, this variant meets the criteria to be classified as pathogenic for MPS I based on the ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert Panel (Specifications Version 1.0.0): PVS1, PM2_Supporting, PM3_Strong, PP4. (Classification approved by the ClinGen Lysosomal Diseases Variant Curation Expert Panel on December 5, 2024) -

Apr 06, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Pathogenic:2
Dec 18, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate that IDUA activity is significantly reduced compared to wildtype (PMID: 9391892); Nonsense variant predicted to result in protein truncation or nonsense mediated decay 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: 25525159, 31298590, 31133280, 29976218, 28676128, 21734815, 28367323, 8019572, 37542767, 9391892, 35141277, 9787109, 23837464, 15081804) -

Nov 17, 2021
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hurler syndrome Pathogenic:1
Jan 26, 2017
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Benign
-0.14
CADD
Pathogenic
35
DANN
Benign
0.93
Eigen
Benign
-0.73
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.43
N
PhyloP100
-0.049
Vest4
0.83
GERP RS
-7.4
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.90
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.90
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs764196171; hg19: chr4-996113; API