rs780596734

chr4-52028101-T-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1_StrongPM2PP3_StrongPP5_Very_Strong

The NM_000232.5(SGCB):c.622-2A>G variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000559 in 1,609,854 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/2 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

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

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

SGCB
NM_000232.5 splice_acceptor

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.87

Variant links:

Genes affected

SGCB (HGNC:10806): (sarcoglycan beta) This gene encodes a member of the sarcoglycan family. Sarcoglycans are transmembrane components in the dystrophin-glycoprotein complex which help stabilize the muscle fiber membranes and link the muscle cytoskeleton to the extracellular matrix. Mutations in this gene have been associated with limb-girdle muscular dystrophy.[provided by RefSeq, Oct 2008]

SGCB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.1368861 fraction of the gene. Cryptic splice site detected, with MaxEntScore 4.5, offset of -35, new splice context is: caattctcacattaatttAGaaa. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. No scorers claiming Benign.

PP5

Variant 4-52028101-T-C is Pathogenic according to our data. Variant chr4-52028101-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 370115.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr4-52028101-T-C is described in Lovd as [Pathogenic]. Variant chr4-52028101-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	Effect	MANE
SGCB	NM_000232.5 linkuse as main transcript	c.622-2A>G	splice_acceptor_variant	ENST00000381431.10
SGCB	XM_047416074.1 linkuse as main transcript	c.412-2A>G	splice_acceptor_variant
SGCB	XM_047416075.1 linkuse as main transcript	c.325-2A>G	splice_acceptor_variant
SGCB	XM_047416076.1 linkuse as main transcript	c.325-2A>G	splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SGCB	ENST00000381431.10 linkuse as main transcript	c.622-2A>G		splice_acceptor_variant		1	NM_000232.5	P1	Q16585-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152202

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

250836

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135650

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000328

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000480

AC:

AN:

1457652

Hom.:

Cov.:

AF XY:

0.00000551

AC XY:

AN XY:

725374

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000541

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152202

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000151

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2E

Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 22, 2024	This sequence change affects an acceptor splice site in intron 4 of the SGCB gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in SGCB are known to be pathogenic (PMID: 15938573, 18285821). This variant is present in population databases (rs780596734, gnomAD 0.003%). Disruption of this splice site has been observed in individuals with limb-girdle muscular dystrophy (PMID: 12566530). ClinVar contains an entry for this variant (Variation ID: 370115). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Nov 24, 2015	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Oct 05, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 08, 2023	- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.55

BayesDel_noAF

Pathogenic

0.34

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.96

FATHMM_MKL

Pathogenic

0.99

MutationTaster

Benign

1.0

D;D

GERP RS

5.3

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.93

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_AL_spliceai

0.99

Position offset: -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