rs1555620214

chr17-80210795-T-C

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000199.5(SGSH):c.1166A>G(p.Asn389Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,722 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N389K) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: SGSH NM_000199.5 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 7.84

Genes affected

SGSH (HGNC:10818): (N-sulfoglucosamine sulfohydrolase) This gene encodes the enzyme sulfamidase; one of several enzymes involved in the lysosomal degradation of heparan sulfate. Mutations in this gene are associated with the lysosomal storage disease mucopolysaccaridosis IIIA, also known as Sanfilippo syndrome A, which results from impaired degradation of heparan sulfate. Transcripts of varying sizes have been reported but their biological validity has not been determined. [provided by RefSeq, Jun 2017]

CARD14 (HGNC:16446): (caspase recruitment domain family member 14) This gene encodes a caspase recruitment domain-containing protein that is a member of the membrane-associated guanylate kinase (MAGUK) family of proteins. Members of this protein family are scaffold proteins that are involved in a diverse array of cellular processes including cellular adhesion, signal transduction and cell polarity control. This protein has been shown to specifically interact with BCL10, a protein known to function as a positive regulator of cell apoptosis and NF-kappaB activation. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-80210794-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 550465.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98
• PP5: Variant 17-80210795-T-C is Pathogenic according to our data. Variant chr17-80210795-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 550252.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SGSH	NM_000199.5	c.1166A>G	p.Asn389Ser	missense_variant	8/8	ENST00000326317.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SGSH	ENST00000326317.11	c.1166A>G	p.Asn389Ser	missense_variant	8/8	1	NM_000199.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151964 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251070 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135868

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000821 AC: 12 AN: 1461758 Hom.: 0 Cov.: 34 AF XY: 0.0000110 AC XY: 8 AN XY: 727170

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: 0.0000108

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151964 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74212

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Mucopolysaccharidosis, MPS-III-A Pathogenic:7

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 20, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Aug 20, 2018	Variant summary: SGSH c.1166A>G (p.Asn389Ser) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. In silico studies also predicted damaging effect for the variant on enzyme structure or activity (Sidhu 2014, Ugrinov 2015). The variant was absent in 246048 control chromosomes (gnomAD). c.1166A>G has been reported in the literature in individuals affected with Mucopolysaccharidosis Type IIIA (Sanfilippo Syndrome A) (Pollard 2013, Shapiro 2016). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, and classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Nov 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Dec 23, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 17, 2024	This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 389 of the SGSH protein (p.Asn389Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with mucopolysaccharidosis type III (PMID: 22976768, 26787381). ClinVar contains an entry for this variant (Variation ID: 550252). 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 SGSH protein function with a positive predictive value of 95%. This variant disrupts the p.Asn389 amino acid residue in SGSH. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11903343, 21061399). 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. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Feb 26, 2022	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.43
BayesDel_addAF	Uncertain	0.060	T
BayesDel_noAF	Benign	-0.15
Cadd	Uncertain	26
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.35	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.50	D
MutationAssessor	Pathogenic	3.2	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.45	T
PROVEAN	Pathogenic	-4.6	D
REVEL	Pathogenic	0.79
Sift	Pathogenic	0.0	D
Sift4G	Benign	0.11	T
Polyphen		1.0	D
Vest4		0.89
MutPred		0.90		Loss of sheet (P = 0.0126);
MVP		0.92
MPC		0.68
ClinPred		1.0	D
GERP RS		4.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.87
gMVP		0.87

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1555620214; hg19: chr17-78184594;