21-43773901-C-T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The ENST00000675996.1(CSTB):​n.1023G>A variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000725 in 386,004 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000085 ( 0 hom. )

Consequence

CSTB
ENST00000675996.1 non_coding_transcript_exon

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.322

Publications

0 publications found
Variant links:
Genes affected
CSTB (HGNC:2482): (cystatin B) The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and kininogens. This gene encodes a stefin that functions as an intracellular thiol protease inhibitor. The protein is able to form a dimer stabilized by noncovalent forces, inhibiting papain and cathepsins l, h and b. The protein is thought to play a role in protecting against the proteases leaking from lysosomes. Evidence indicates that mutations in this gene are responsible for the primary defects in patients with progressive myoclonic epilepsy (EPM1). One type of mutation responsible for EPM1 is the expansion in the promoter region of this gene of a CCCCGCCCCGCG repeat from 2-3 copies to 30-78 copies. [provided by RefSeq, Jul 2016]
CSTB Gene-Disease associations (from GenCC):
  • Unverricht-Lundborg syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
  • keratolytic winter erythema
    Inheritance: AD Classification: MODERATE Submitted by: PanelApp Australia
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen
  • autosomal recessive hypohidrotic ectodermal dysplasia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.82).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CSTBNM_000100.4 linkc.*301G>A downstream_gene_variant ENST00000291568.7 NP_000091.1 P04080Q76LA1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CSTBENST00000675996.1 linkn.1023G>A non_coding_transcript_exon_variant Exon 3 of 3
CSTBENST00000640406.1 linkc.*673G>A 3_prime_UTR_variant Exon 2 of 2 2 ENSP00000492672.1 A0A1W2PS52
CSTBENST00000639959.1 linkc.*301G>A 3_prime_UTR_variant Exon 2 of 2 5 ENSP00000492123.1 A0A1W2PQG6
CSTBENST00000291568.7 linkc.*301G>A downstream_gene_variant 1 NM_000100.4 ENSP00000291568.6 P04080

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152068
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.0000855
AC:
20
AN:
233936
Hom.:
0
Cov.:
2
AF XY:
0.0000702
AC XY:
9
AN XY:
128206
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
6488
American (AMR)
AF:
0.00
AC:
0
AN:
11908
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
5710
East Asian (EAS)
AF:
0.00
AC:
0
AN:
10382
South Asian (SAS)
AF:
0.00
AC:
0
AN:
41572
European-Finnish (FIN)
AF:
0.000102
AC:
1
AN:
9772
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
2382
European-Non Finnish (NFE)
AF:
0.000142
AC:
19
AN:
133778
Other (OTH)
AF:
0.00
AC:
0
AN:
11944
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152068
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74300
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41376
American (AMR)
AF:
0.0000655
AC:
1
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000718

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Unverricht-Lundborg syndrome Uncertain:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.82
CADD
Benign
2.9
DANN
Benign
0.56
PhyloP100
-0.32
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.2

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: rs886057111; hg19: chr21-45193782; API