7-94603331-AT-ATT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_003919.3(SGCE):c.783_784insA(p.Phe262IlefsTer8) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,586 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. K261K) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SGCE NM_003919.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 0.150

Genes affected

SGCE (HGNC:10808): (sarcoglycan epsilon) This gene encodes the epsilon member of the sarcoglycan family. Sarcoglycans are transmembrane proteins that are components of the dystrophin-glycoprotein complex, which link the actin cytoskeleton to the extracellular matrix. Unlike other family members which are predominantly expressed in striated muscle, the epsilon sarcoglycan is more broadly expressed. Mutations in this gene are associated with myoclonus-dystonia syndrome. This gene is imprinted, with preferential expression from the paternal allele. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. A pseudogene associated with this gene is located on chromosome 2. [provided by RefSeq, Oct 2016]

CASD1 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-94603331-A-AT is Pathogenic according to our data. Variant chr7-94603331-A-AT is described in ClinVar as [Pathogenic]. Clinvar id is 397531.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SGCE	NM_003919.3	c.783_784insA	p.Phe262IlefsTer8	frameshift_variant	6/11	ENST00000648936.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SGCE	ENST00000648936.2	c.783_784insA	p.Phe262IlefsTer8	frameshift_variant	6/11		NM_003919.3	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460586 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726530

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Myoclonic dystonia 11 Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München	Jan 30, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Center of Genomic medicine, Geneva, University Hospital of Geneva	Aug 26, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Sep 06, 2021	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 397531). This premature translational stop signal has been observed in individual(s) with myoclonus-dystonia (PMID: 23677909). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Phe262Ilefs*8) in the SGCE gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SGCE are known to be pathogenic (PMID: 12821748, 15389977, 17853490, 24297365). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		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

Other links and lift over

dbSNP: rs1189469219; hg19: chr7-94232643;