Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_003919.3(SGCE):c.1114C>T(p.Arg372*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000248 in 1,613,714 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.
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:16014): (CAS1 domain containing 1) Enables N-acetylneuraminate 7-O(or 9-O)-acetyltransferase activity. Involved in carbohydrate metabolic process. Is integral component of Golgi membrane. [provided by Alliance of Genome Resources, Apr 2022]
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 7-94598914-G-A is Pathogenic according to our data. Variant chr7-94598914-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 5776.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-94598914-G-A is described in Lovd as [Pathogenic].
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This premature translational stop signal has been observed in individuals with myoclonus dystonia (PMID: 15728306, 18205193, 23677909). It has also been observed to segregate with disease in related individuals. For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 5776). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Arg372*) 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). -
not provided Pathogenic:1
Apr 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter