rs1554537841

Variant names:

• chr8-43197900-C-G
• rs1554537841
• NM_152419.3:c.1674C>G

Your query was ambiguous. Multiple possible variants found:

• chr8-43197900-C-G
• chr8-43197900-C-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_152419.3(HGSNAT):​c.1674C>G​(p.Tyr558*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,674 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 Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HGSNAT NM_152419.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 0.507
• Publications: 2 publications found

Genes affected

HGSNAT (HGNC:26527): (heparan-alpha-glucosaminide N-acetyltransferase) This gene encodes a lysosomal acetyltransferase, which is one of several enzymes involved in the lysosomal degradation of heparin sulfate. Mutations in this gene are associated with Sanfilippo syndrome C, one type of the lysosomal storage disease mucopolysaccaridosis III, which results from impaired degradation of heparan sulfate. [provided by RefSeq, Jan 2009]

HGSNAT Gene-Disease associations (from GenCC):

• inherited retinal dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mucopolysaccharidosis type 3

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• mucopolysaccharidosis type 3C

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, G2P, ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa 73

  Inheritance: AR Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-43197900-C-G is Pathogenic according to our data. Variant chr8-43197900-C-G is described in ClinVar as Pathogenic. ClinVar VariationId is 553553.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_152419.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HGSNAT	NM_152419.3	MANE Select	c.1674C>G	p.Tyr558*	stop_gained	Exon 17 of 18	NP_689632.2
	HGSNAT	NM_001363227.2		c.1761C>G	p.Tyr587*	stop_gained	Exon 18 of 19	NP_001350156.1
	HGSNAT	NM_001363228.2		c.1482C>G	p.Tyr494*	stop_gained	Exon 15 of 16	NP_001350157.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HGSNAT	ENST00000379644.9	TSL:2 MANE Select	c.1674C>G	p.Tyr558*	stop_gained	Exon 17 of 18	ENSP00000368965.4	Q68CP4-2
	HGSNAT	ENST00000519705.1	TSL:1	n.990C>G		non_coding_transcript_exon	Exon 3 of 4
	HGSNAT	ENST00000902460.1		c.1875C>G	p.Tyr625*	stop_gained	Exon 18 of 19	ENSP00000572519.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461674 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 727116

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53398

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111852

Other (OTH) AF: 0.00 AC: 0 AN: 60374

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Mucopolysaccharidosis, MPS-III-C (1)
1	-	-	Mucopolysaccharidosis, MPS-III-C;C4225287:Retinitis pigmentosa 73 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.39
FATHMM_MKL	Uncertain	0.92	D
PhyloP100		0.51
Vest4		0.91
GERP RS		2.8
Mutation Taster		=1/199	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1554537841; hg19: chr8-43053043;