rs1553917627

Positions:

• chr4-1003606-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP3_Strong PP5

The NM_000203.5(IDUA):​c.1708G>C​(p.Asp570His) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,460,206 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D570G) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: IDUA NM_000203.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 6.89

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-1003607-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1980496.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.969
• PP5: Variant 4-1003606-G-C is Pathogenic according to our data. Variant chr4-1003606-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 551300.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
IDUA	NM_000203.5	c.1708G>C	p.Asp570His	missense_variant	12/14	ENST00000514224.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
IDUA	ENST00000514224.2	c.1708G>C	p.Asp570His	missense_variant	12/14	2	NM_000203.5	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460206 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 726406

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Mucopolysaccharidosis type 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 17, 2023

This missense change has been observed in individual(s) with mucopolysaccharidosis type I (PMID: 25558755). ClinVar contains an entry for this variant (Variation ID: 551300). 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 IDUA protein function. This variant disrupts the p.Asp570 amino acid residue in IDUA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 31991612). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces aspartic acid, which is acidic and polar, with histidine, which is basic and polar, at codon 570 of the IDUA protein (p.Asp570His). -

Hurler syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Counsyl

Mar 29, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.070
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.73	D;.
Eigen	Pathogenic	0.72
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Benign	0.81	T;.
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Uncertain	0.56	D
MutationAssessor	Uncertain	2.2	M;.
MutationTaster	Benign	0.73	D;D;D
PrimateAI	Uncertain	0.62	T
PROVEAN	Pathogenic	-4.4	D;D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0010	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.99	D;.
Vest4		0.89
MVP		0.91
MPC		0.82
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.93
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		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: rs1553917627; hg19: chr4-997394;