17-80220226-C-A

Position:

chr17-80220226-C-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong

The NM_000199.5(SGSH):c.88G>T(p.Ala30Ser) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000022 in 1,366,088 control chromosomes in the GnomAD database, with no homozygous occurrence. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A30P) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

SGSH
NM_000199.5 missense, splice_region

Scores

Splicing: ADA: 1.000

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.900

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]

SGSH links:

SLC26A11 (HGNC:14471): (solute carrier family 26 member 11) This gene encodes a member of the solute linked carrier 26 family of anion exchangers. Members of this family of proteins are essential for numerous cellular functions including homeostasis and intracellular electrolyte balance. The encoded protein is a sodium independent sulfate transporter that is sensitive to the anion exchanger inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Oct 2009]

SLC26A11 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PM1

In a strand (size 8) in uniprot entity SPHM_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_000199.5

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr17-80220226-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1350122.Status of the report is criteria_provided_single_submitter, 1 stars.

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SGSH	NM_000199.5 linkuse as main transcript	c.88G>T	p.Ala30Ser	missense_variant, splice_region_variant	1/8	ENST00000326317.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SGSH	ENST00000326317.11 linkuse as main transcript	c.88G>T	p.Ala30Ser	missense_variant, splice_region_variant	1/8	1	NM_000199.5	P1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000861

AC:

AN:

116146

Hom.:

AF XY:

0.0000156

AC XY:

AN XY:

63992

show subpopulations

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:

0.0000230

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000220

AC:

AN:

1366088

Hom.:

Cov.:

AF XY:

0.00000445

AC XY:

AN XY:

673732

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:

0.00000280

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-III-A

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 22, 2022

This sequence change affects codon 30 of the SGSH mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the SGSH protein. This variant also falls at the last nucleotide of exon 1, which is part of the consensus splice site for this exon. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with SGSH-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant disrupts the c.88G nucleotide in the SGSH gene. Other variant(s) that disrupt this nucleotide have been determined to be pathogenic (PMID: 22976768, 26331342). This suggests that this nucleotide is clinically significant, and that variants that disrupt this position are likely to be disease-causing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Uncertain

0.13

BayesDel_noAF

Uncertain

-0.010

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.64

D;.;.

Eigen

Benign

0.084

Eigen_PC

Benign

0.077

FATHMM_MKL

Uncertain

0.84

LIST_S2

Uncertain

0.92

D;T;D

M_CAP

Pathogenic

0.82

MetaRNN

Uncertain

0.60

D;T;D

MetaSVM

Pathogenic

0.83

MutationAssessor

Benign

1.6

L;.;.

MutationTaster

Benign

1.0

D;D;N

PrimateAI

Pathogenic

0.82

PROVEAN

Benign

-2.0

N;.;.

REVEL

Uncertain

0.63

Sift

Benign

0.084

T;.;.

Sift4G

Uncertain

0.012

D;D;.

Polyphen

0.37

B;.;.

Vest4

0.57

MutPred

0.52

Gain of sheet (P = 4e-04);Gain of sheet (P = 4e-04);Gain of sheet (P = 4e-04);

MVP

0.93

MPC

0.18

ClinPred

0.79

GERP RS

3.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.6

Varity_R

0.52

gMVP

0.81

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.95

SpliceAI score (max)

0.010

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

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over