NM_000100.4:c.27G>C

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2BP4_StrongBP6_ModerateBP7

The NM_000100.4(CSTB):c.27G>C(p.Thr9Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000262 in 1,528,504 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 Likely benign (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000015 ( 0 hom. )

Consequence

CSTB
NM_000100.4 synonymous

Scores

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: -0.839

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

CSTB links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.66).

BP6

Variant 21-43776243-C-G is Benign according to our data. Variant chr21-43776243-C-G is described in ClinVar as Likely_benign. ClinVar VariationId is 414880.Status of the report is criteria_provided_single_submitter, 1 stars.

BP7

Synonymous conserved (PhyloP=-0.839 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000100.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CSTB	NM_000100.4	MANE Select	c.27G>C	p.Thr9Thr	synonymous	Exon 1 of 3	NP_000091.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
CSTB	ENST00000291568.7	TSL:1 MANE Select	c.27G>C	p.Thr9Thr	synonymous	Exon 1 of 3	ENSP00000291568.6
CSTB	ENST00000640406.1	TSL:2	c.27G>C	p.Thr9Thr	synonymous	Exon 1 of 2	ENSP00000492672.1
CSTB	ENST00000675996.1		n.88G>C		non_coding_transcript_exon	Exon 1 of 3

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

152060

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000145

AC:

AN:

1376444

Hom.:

Cov.:

AF XY:

0.00000147

AC XY:

AN XY:

679024

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:

AN:

29492

American (AMR)

AF:

0.00

AC:

AN:

34690

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

24670

East Asian (EAS)

AF:

0.00

AC:

AN:

34386

South Asian (SAS)

AF:

0.00

AC:

AN:

77534

European-Finnish (FIN)

AF:

0.00

AC:

AN:

40270

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5406

European-Non Finnish (NFE)

AF:

9.32e-7

AC:

AN:

1072690

Other (OTH)

AF:

0.0000175

AC:

AN:

57306

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0296732), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.400

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000132

AC:

AN:

152060

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74282

show subpopulations

African (AFR)

AF:

0.0000483

AC:

AN:

41412

American (AMR)

AF:

0.00

AC:

AN:

15274

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5160

South Asian (SAS)

AF:

0.00

AC:

AN:

4832

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10602

Middle Eastern (MID)

AF:

0.00

AC:

AN:

314

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67994

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.500

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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.:

Bravo

AF:

0.00000378

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy

Benign:1

Jan 30, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.66

CADD

Benign

6.2

(source)

DANN

Benign

0.68

PhyloP100

-0.84

PromoterAI

0.047

Neutral

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over