21-43773915-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.1009G>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 0.0000488 in 409,426 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 0.000040 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000054 ( 0 hom. )

Consequence

CSTB
ENST00000675996.1 non_coding_transcript_exon

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -2.39

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=-0.87).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CSTBNM_000100.4 linkc.*287G>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.1009G>A non_coding_transcript_exon_variant Exon 3 of 3
CSTBENST00000640406.1 linkc.*659G>A 3_prime_UTR_variant Exon 2 of 2 2 ENSP00000492672.1 A0A1W2PS52
CSTBENST00000639959.1 linkc.*287G>A 3_prime_UTR_variant Exon 2 of 2 5 ENSP00000492123.1 A0A1W2PQG6
CSTBENST00000291568.7 linkc.*287G>A downstream_gene_variant 1 NM_000100.4 ENSP00000291568.6 P04080

Frequencies

GnomAD3 genomes
AF:
0.0000396
AC:
6
AN:
151494
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000487
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.000193
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
GnomAD4 exome
AF:
0.0000543
AC:
14
AN:
257932
Hom.:
0
Cov.:
3
AF XY:
0.0000356
AC XY:
5
AN XY:
140260
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
7322
American (AMR)
AF:
0.00
AC:
0
AN:
12602
Ashkenazi Jewish (ASJ)
AF:
0.000755
AC:
5
AN:
6624
East Asian (EAS)
AF:
0.00
AC:
0
AN:
12514
South Asian (SAS)
AF:
0.00
AC:
0
AN:
41992
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10862
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
2536
European-Non Finnish (NFE)
AF:
0.0000600
AC:
9
AN:
149970
Other (OTH)
AF:
0.00
AC:
0
AN:
13510
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.532
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.0000396
AC:
6
AN:
151494
Hom.:
0
Cov.:
33
AF XY:
0.0000406
AC XY:
3
AN XY:
73966
show subpopulations
African (AFR)
AF:
0.0000487
AC:
2
AN:
41092
American (AMR)
AF:
0.00
AC:
0
AN:
15214
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3468
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10456
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67946
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000491

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
-0.87
CADD
Benign
0.030
DANN
Benign
0.80
PhyloP100
-2.4
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: rs768173714; hg19: chr21-45193796; API