rs398123244

Positions:

• chr17-80210816-C-CGGCGCT

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PM4 PP5

The NM_000199.5(SGSH):​c.1144_1145insAGCGCC​(p.His381_Arg382insGlnArg) variant causes a conservative inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000044 in 1,613,840 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000047 (0 hom.)
• Consequence: SGSH NM_000199.5 conservative_inframe_insertion
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5 U:1
• Conservation: PhyloP100: 0.589

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_000199.5.
• PP5: Variant 17-80210816-C-CGGCGCT is Pathogenic according to our data. Variant chr17-80210816-C-CGGCGCT is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 92608.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=3, Likely_pathogenic=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SGSH	NM_000199.5	c.1144_1145insAGCGCC	p.His381_Arg382insGlnArg	conservative_inframe_insertion	8/8	ENST00000326317.11	NP_000190.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SGSH	ENST00000326317.11	c.1144_1145insAGCGCC	p.His381_Arg382insGlnArg	conservative_inframe_insertion	8/8	1	NM_000199.5	ENSP00000314606.6

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152138 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

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: 0.0000159 AC: 4 AN: 251032 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135850

Gnomad AFR exome AF: 0.0000616

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: 0.0000265

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000472 AC: 69 AN: 1461702 Hom.: 0 Cov.: 34 AF XY: 0.0000426 AC XY: 31 AN XY: 727136

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: 0.0000621

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152138 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74310

Gnomad4 AFR AF: 0.0000241

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

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:5 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Mucopolysaccharidosis, MPS-III-A Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 09, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jun 29, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 13, 2024	This variant, c.1144_1145insAGCGCC, results in the insertion of 2 amino acid(s) of the SGSH protein (p.His381_Arg382insGlnArg), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs398123244, gnomAD 0.007%). This variant has been observed in individual(s) with mucopolysaccharidosis type III (PMID: 11182930, 27590925). This variant is also known as 1156ins6. ClinVar contains an entry for this variant (Variation ID: 92608). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 12, 2013	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 14, 2022	In-frame insertion of 2 amino acids in a non-repeat region; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 21963080, 11182930, 27590925, 34991944) -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs398123244; hg19: chr17-78184615;