rs777956287

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_000199.5(SGSH):​c.1135delG​(p.Val379CysfsTer34) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000744 in 1,613,900 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

SGSH
NM_000199.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 0.899
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 6 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 17-80210825-AC-A is Pathogenic according to our data. Variant chr17-80210825-AC-A is described in ClinVar as [Pathogenic]. Clinvar id is 280988.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-80210825-AC-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SGSHNM_000199.5 linkc.1135delG p.Val379CysfsTer34 frameshift_variant Exon 8 of 8 ENST00000326317.11 NP_000190.1 P51688

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SGSHENST00000326317.11 linkc.1135delG p.Val379CysfsTer34 frameshift_variant Exon 8 of 8 1 NM_000199.5 ENSP00000314606.6 P51688

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152210
Hom.:
0
Cov.:
33
show subpopulations
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
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461690
Hom.:
0
Cov.:
34
AF XY:
0.00000963
AC XY:
7
AN XY:
727132
show subpopulations
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:
0.00000899
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152210
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74356
show subpopulations
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:
0.00000378

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-III-A Pathogenic:6
Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

- -

Feb 16, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: SGSH c.1135delG (p.Val379CysfsX34) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant was absent in 250996 control chromosomes. c.1135delG has been reported in the literature in multiple individuals affected with Mucopolysaccharidosis Type IIIA (Sanfilippo Syndrome A) (example, Weber_1997, Chistiakov_2014). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in the expression of a truncated protein that is degraded in the ER prior to sorting site in the Golgi (Muschol_2004). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Mar 27, 2024
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 07, 2021
Genome-Nilou Lab
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 20, 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.Val379Cysfs*34) in the SGSH gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 124 amino acid(s) of the SGSH protein. This variant is present in population databases (rs777956287, gnomAD 0.007%). This premature translational stop signal has been observed in individual(s) with mucopolysaccharidosis type III (PMID: 9285796, 15146460, 24875751). This variant is also known as delG1147 CCGT->CC-T. ClinVar contains an entry for this variant (Variation ID: 280988). For these reasons, this variant has been classified as Pathogenic. -

May 07, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:2
Sep 02, 2016
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

SGSH: PM3:Strong, PVS1:Strong, PM2 -

Sanfilippo syndrome Pathogenic:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.1135delG (p.Val379CysfsTer34) variant (also known as delG1147) results in a frameshift, and is predicted to result in premature termination of the protein. The p.Val379CysfsTer variant has been identified in at least six patients with mucopolysaccharidosis type III, including one in a homozygous state and five in a compound heterozygous state (Weber et al. 1997; Muschol et al. 2004; Chistiakov et al. 2014). Control data are unavailable for this variant, which is not found in the 1000 Genomes Project, the Exome Sequencing Project, or the Exome Aggregation Consortium. Muschol et al. (2004) demonstrated that the p.Val379CysfsTer34 variant protein is degraded in the endoplasmic reticulum prior to the sorting site in the Golgi apparatus. In addition, Chistiakov et al. (2014) showed that the variant resulted in markedly reduced enzyme activity in patients compared to control levels. Patients who were compound heterozygous for the p.Val379CysfsTer34 variant and a common missense variant (p.Arg74Cys), had residual SGSH activity which was intermediate between the enzymatic activity in individuals who were homozygous for the p.Arg74Cys variant and those who were compound heterozygous for the p.Arg74Cys variant. Due to the potential impact of frameshift variants and the supporting evidence from the literature, the p.Val379CysfsTer34 variant is classified as pathogenic for mucopolysaccharidosis type III. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.22
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.22
Position offset: -5

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs777956287; hg19: chr17-78184624; API