rs754875934

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PP3_ModeratePP5

The NM_001363229.2(HGSNAT):​c.-464A>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000181 in 1,600,428 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

HGSNAT
NM_001363229.2 5_prime_UTR_premature_start_codon_gain

Scores

4
8
4
Splicing: ADA: 0.9910
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6U:2

Conservation

PhyloP100: 3.02
Variant links:
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]

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.866
PP5
Variant 8-43158710-A-T is Pathogenic according to our data. Variant chr8-43158710-A-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 208815.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=3, Likely_pathogenic=1}. Variant chr8-43158710-A-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
HGSNATNM_152419.3 linkuse as main transcriptc.370A>T p.Arg124Trp missense_variant, splice_region_variant 3/18 ENST00000379644.9 NP_689632.2 Q68CP4-2Q8IVU6

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
HGSNATENST00000379644.9 linkuse as main transcriptc.370A>T p.Arg124Trp missense_variant, splice_region_variant 3/182 NM_152419.3 ENSP00000368965.4 Q68CP4-2
HGSNATENST00000520704.1 linkuse as main transcriptn.220A>T splice_region_variant, non_coding_transcript_exon_variant 3/101 ENSP00000429109.1 E5RJC4
HGSNATENST00000517319.1 linkuse as main transcriptn.235-213A>T intron_variant 4 ENSP00000430032.1 E5RH11

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152216
Hom.:
0
Cov.:
32
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000208
AC:
5
AN:
240818
Hom.:
0
AF XY:
0.0000306
AC XY:
4
AN XY:
130602
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000212
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000272
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000186
AC:
27
AN:
1448212
Hom.:
0
Cov.:
31
AF XY:
0.0000237
AC XY:
17
AN XY:
718558
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.000195
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000181
Gnomad4 OTH exome
AF:
0.0000334
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74366
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:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.0000302
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.00000828
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:6Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Retinitis pigmentosa 73 Pathogenic:2
Pathogenic, no assertion criteria providedliterature onlyOMIMJul 01, 2015- -
Likely pathogenic, criteria provided, single submitterclinical testingInstitute of Human Genetics, University of Leipzig Medical CenterNov 29, 2022This variant was identified as compound heterozygous with NM_152419.3:c.1843G>A._x000D_ Criteria applied: PS3, PM3_STR, PM2_SUP -
Mucopolysaccharidosis, MPS-III-C Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Nov 11, 2021NM_152419.2(HGSNAT):c.370A>T(R124W) is a missense variant classified as a variant of uncertain significance in the context of mucopolysaccharidosis type IIIC. R124W has not been observed in cases with relevant disease. Functional assessments of this variant are available in the literature (PMID: 25859010). R124W has been observed in population frequency databases (gnomAD ASJ 0.02%). In summary, there is insufficient evidence to classify NM_152419.2(HGSNAT):c.370A>T(R124W) as pathogenic or benign. Please note: this variant was assessed in the context of healthy population screening. -
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
Mucopolysaccharidosis, MPS-III-C;C4225287:Retinitis pigmentosa 73 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 09, 2024This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 124 of the HGSNAT protein (p.Arg124Trp). RNA analysis indicates that this missense change induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs754875934, gnomAD 0.02%). This missense change has been observed in individuals with retinitis pigmentosa (PMID: 25859010; Invitae). ClinVar contains an entry for this variant (Variation ID: 208815). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Studies have shown that this missense change results in partial skipping of exon 3 and introduces a premature termination codon (PMID: 25859010). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGeneDxJan 28, 2022Missense variant demonstrated to result in partial exon skipping in a gene for which loss-of-function is a known mechanism of disease (Haer-Wigman et al., 2015); This variant is associated with the following publications: (PMID: 25859010, 31456290, 32770643, 34426522) -
Retinal dystrophy Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBlueprint GeneticsJan 18, 2019- -
Retinitis pigmentosa Pathogenic:1
Pathogenic, no assertion criteria providedresearchSharon lab, Hadassah-Hebrew University Medical CenterJun 23, 2019- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
32
DANN
Uncertain
1.0
Eigen
Benign
0.16
Eigen_PC
Benign
0.048
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Uncertain
0.90
D
M_CAP
Uncertain
0.23
D
MetaRNN
Pathogenic
0.87
D
MetaSVM
Uncertain
0.53
D
PrimateAI
Benign
0.47
T
PROVEAN
Uncertain
-3.7
D
REVEL
Pathogenic
0.65
Sift
Uncertain
0.0060
D
Sift4G
Uncertain
0.011
D
Vest4
0.70
MVP
0.91
MPC
0.51
ClinPred
0.84
D
GERP RS
2.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
gMVP
0.65

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.99
dbscSNV1_RF
Pathogenic
0.94
SpliceAI score (max)
0.30
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.30
Position offset: -7

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: rs754875934; hg19: chr8-43013853; API