rs1238128027

chr4-1001522-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000203.5(IDUA):c.548C>G(p.Pro183Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,460,986 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. P183A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • 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: 5.90

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.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 9 uncertain in NM_000203.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.952
• PP5: Variant 4-1001522-C-G is Pathogenic according to our data. Variant chr4-1001522-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 551348.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
IDUA	NM_000203.5	c.548C>G	p.Pro183Arg	missense_variant	5/14	ENST00000514224.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
IDUA	ENST00000514224.2	c.548C>G	p.Pro183Arg	missense_variant	5/14	2	NM_000203.5	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250916 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135818

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 SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460986 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726790

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

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

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Aug 22, 2022

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. 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. ClinVar contains an entry for this variant (Variation ID: 551348). This missense change has been observed in individual(s) with mucopolysaccharidosis type I (PMID: 9427149, 12203999). This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 183 of the IDUA protein (p.Pro183Arg). -

Hurler syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Counsyl

Apr 04, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.54
Cadd	Pathogenic	28
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;.;D;D;.
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.94	D;D;.;.;.
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D
MetaSVM	Uncertain	-0.078	T
MutationAssessor	Uncertain	2.7	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Pathogenic	-8.0	D;D;D;D;D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D;D
Polyphen		1.0	D;.;.;.;.
Vest4		0.92
MutPred		0.75		.;Gain of solvent accessibility (P = 0.007);.;.;.;
MVP		0.99
MPC		0.78
ClinPred		1.0	D
GERP RS		4.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.93
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1238128027; hg19: chr4-995310;