chr21-43774762-A-G

Position:

chr21-43774762-A-G

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000100.4(CSTB):c.67-3T>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000834 in 1,610,974 control chromosomes in the GnomAD database, including 6 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0044 ( 4 hom., cov: 33)

Exomes 𝑓: 0.00046 ( 2 hom. )

Consequence

CSTB
NM_000100.4 splice_region, intron

Scores

Splicing: ADA: 0.00009725

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: 0.0380

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 links:

CSTB (HGNC:):

CSTB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.77).

BP6

Variant 21-43774762-A-G is Benign according to our data. Variant chr21-43774762-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 137037.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00443 (675/152330) while in subpopulation AFR AF= 0.0151 (627/41574). AF 95% confidence interval is 0.0141. There are 4 homozygotes in gnomad4. There are 309 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High Homozygotes in GnomAd4 at 4 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CSTB	NM_000100.4 linkuse as main transcript	c.67-3T>C		splice_region_variant, intron_variant		ENST00000291568.7	NP_000091.1	P04080Q76LA1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CSTB	ENST00000291568.7 linkuse as main transcript	c.67-3T>C		splice_region_variant, intron_variant		1	NM_000100.4	ENSP00000291568.6		P04080

Frequencies

GnomAD3 genomes

AF:

0.00442

AC:

673

AN:

152212

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0151

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00183

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00316

Gnomad NFE

AF:

0.000103

Gnomad OTH

AF:

0.00526

GnomAD3 exomes

AF:

0.00111

AC:

278

AN:

251432

Hom.:

AF XY:

0.000802

AC XY:

109

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.0145

Gnomad AMR exome

AF:

0.000954

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000527

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000459

AC:

669

AN:

1458644

Hom.:

Cov.:

AF XY:

0.000409

AC XY:

297

AN XY:

725928

show subpopulations

Gnomad4 AFR exome

AF:

0.0152

Gnomad4 AMR exome

AF:

0.00110

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000568

Gnomad4 OTH exome

AF:

0.000730

GnomAD4 genome

AF:

0.00443

AC:

675

AN:

152330

Hom.:

Cov.:

AF XY:

0.00415

AC XY:

309

AN XY:

74496

show subpopulations

Gnomad4 AFR

AF:

0.0151

Gnomad4 AMR

AF:

0.00183

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000103

Gnomad4 OTH

AF:

0.00520

Alfa

AF:

0.00145

Hom.:

Bravo

AF:

0.00458

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.000109

EpiControl

AF:

0.000178

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia	Apr 14, 2015	- -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Nov 21, 2013	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 04, 2018

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Unverricht-Lundborg syndrome

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

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 and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

not provided

Benign:1

Likely benign, criteria provided, single submitter

not provided

Breakthrough Genomics, Breakthrough Genomics

- -

Progressive myoclonic epilepsy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 29, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.77

CADD

Benign

3.5

DANN

Benign

0.77

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.000097

dbscSNV1_RF

Benign

0.0080

SpliceAI score (max)

0.020

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over