NM_000100.4:c.45G>A

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_ModerateBP6BP7BS1

The NM_000100.4(CSTB):​c.45G>A​(p.Glu15Glu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000143 in 1,532,286 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00015 ( 1 hom. )

Consequence

CSTB
NM_000100.4 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 0.574

Publications

1 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: Benign. The variant received -8 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.36).
BP6
Variant 21-43776225-C-T is Benign according to our data. Variant chr21-43776225-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 382295.
BP7
Synonymous conserved (PhyloP=0.574 with no splicing effect.
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.000092 (14/152240) while in subpopulation EAS AF = 0.00213 (11/5162). AF 95% confidence interval is 0.00119. There are 0 homozygotes in GnomAd4. There are 5 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CSTBNM_000100.4 linkc.45G>A p.Glu15Glu synonymous_variant Exon 1 of 3 ENST00000291568.7 NP_000091.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CSTBENST00000291568.7 linkc.45G>A p.Glu15Glu synonymous_variant Exon 1 of 3 1 NM_000100.4 ENSP00000291568.6
CSTBENST00000640406.1 linkc.45G>A p.Glu15Glu synonymous_variant Exon 1 of 2 2 ENSP00000492672.1
CSTBENST00000639959.1 linkc.12G>A p.Glu4Glu synonymous_variant Exon 1 of 2 5 ENSP00000492123.1
CSTBENST00000675996.1 linkn.106G>A non_coding_transcript_exon_variant Exon 1 of 3

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152132
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00212
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:
0.000279
AC:
36
AN:
128894
AF XY:
0.000270
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00365
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000149
AC:
205
AN:
1380046
Hom.:
1
Cov.:
31
AF XY:
0.000151
AC XY:
103
AN XY:
681040
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
29958
American (AMR)
AF:
0.00
AC:
0
AN:
35172
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
24844
East Asian (EAS)
AF:
0.00569
AC:
199
AN:
34968
South Asian (SAS)
AF:
0.00
AC:
0
AN:
78054
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
39496
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5302
European-Non Finnish (NFE)
AF:
0.00000279
AC:
3
AN:
1074770
Other (OTH)
AF:
0.0000522
AC:
3
AN:
57482
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
14
28
41
55
69
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
4
8
12
16
20
<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:
0.0000920
AC:
14
AN:
152240
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74432
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41556
American (AMR)
AF:
0.000131
AC:
2
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00213
AC:
11
AN:
5162
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67986
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.0000907

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:2
Revision: criteria provided, conflicting classifications
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. -

not provided Benign:1
Apr 02, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Progressive myoclonic epilepsy Benign:1
Nov 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.36
CADD
Benign
11
DANN
Benign
0.87
PhyloP100
0.57
PromoterAI
-0.088
Neutral
Mutation Taster
=100/0
polymorphism

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: rs1057521317; hg19: chr21-45196106; COSMIC: COSV52366781; API