7-65967863-C-T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000181.4(GUSB):​c.1521G>A​(p.Trp507*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000249 in 1,605,508 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: 𝑓 0.000013 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

GUSB
NM_000181.4 stop_gained

Scores

4
2
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.79

Publications

8 publications found
Variant links:
Genes affected
GUSB (HGNC:4696): (glucuronidase beta) This gene encodes a hydrolase that degrades glycosaminoglycans, including heparan sulfate, dermatan sulfate, and chondroitin-4,6-sulfate. The enzyme forms a homotetramer that is localized to the lysosome. Mutations in this gene result in mucopolysaccharidosis type VII. Alternative splicing results in multiple transcript variants. There are many pseudogenes of this locus in the human genome.[provided by RefSeq, May 2014]
GUSB Gene-Disease associations (from GenCC):
  • mucopolysaccharidosis type 7
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Genomics England PanelApp, ClinGen, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 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 7-65967863-C-T is Pathogenic according to our data. Variant chr7-65967863-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 900.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GUSBNM_000181.4 linkc.1521G>A p.Trp507* stop_gained Exon 10 of 12 ENST00000304895.9 NP_000172.2 P08236-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GUSBENST00000304895.9 linkc.1521G>A p.Trp507* stop_gained Exon 10 of 12 1 NM_000181.4 ENSP00000302728.4 P08236-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152172
Hom.:
0
Cov.:
31
show subpopulations
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
GnomAD2 exomes
AF:
0.00000817
AC:
2
AN:
244666
AF XY:
0.00000753
show subpopulations
Gnomad AFR exome
AF:
0.0000617
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000138
AC:
2
AN:
1453336
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
723420
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
45146
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111804
Other (OTH)
AF:
0.00
AC:
0
AN:
60344
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00233887), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.350
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152172
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15262
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Mucopolysaccharidosis type 7 Pathogenic:4
Mar 29, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GUSB c.1521G>A (p.Trp507X) 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 allele was found at a frequency of 1.1e-05 in 270504 control chromosomes. This frequency is not higher than expected for a pathogenic variant in GUSB causing Mucopolysaccharidosis Type VI (Sly Syndrome) (1.1e-05 vs 0.0011), allowing no conclusion about variant significance. c.1521G>A has been reported in the literature in two individuals affected with severe Mucopolysaccharidosis Type VI (Sly Syndrome) (Vervoort 1996, Yamada 1995). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence showing that B-glucuronidase enzyme activity of the variant allele was less than 10% of a normal control (Yamada 1995). No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as pathogenic. -

Apr 01, 1995
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Jun 30, 2019
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Dec 02, 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.Trp507*) in the GUSB gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GUSB are known to be pathogenic (PMID: 19224584). This variant is present in population databases (rs121918179, gnomAD 0.008%). This premature translational stop signal has been observed in individual(s) with mucopolysaccharidosis VII (PMID: 7633414). This variant is also known as W507X. ClinVar contains an entry for this variant (Variation ID: 900). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1
Sep 05, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Published functional studies found this variant is associated with significantly reduced enzyme activity (Yamada S et al., 1995); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25525159, 34426522, 19224584, 7633414, 8644704) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.62
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Pathogenic
0.94
Eigen_PC
Pathogenic
0.82
FATHMM_MKL
Uncertain
0.95
D
PhyloP100
7.8
Vest4
0.90
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs121918179; hg19: chr7-65432850; API