Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_003919.3(SGCE):c.825+1_825+2delGT variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).
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]
Our verdict: Pathogenic. The variant received 18 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 7-94603287-TAC-T is Pathogenic according to our data. Variant chr7-94603287-TAC-T is described in ClinVar as Pathogenic. ClinVar VariationId is 464161.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
This sequence change affects a donor splice site in intron 6 of the SGCE 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 SGCE are known to be pathogenic (PMID: 12821748, 15389977, 17853490, 24297365). This variant is not present in population databases (ExAC no frequency). Disruption of this splice site has been observed in individual(s) with SGCE-related conditions (PMID: 29607243, 11528394). ClinVar contains an entry for this variant (Variation ID: 464161). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. For these reasons, this variant has been classified as Pathogenic. -
not providedPathogenic:1
Nov 21, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing
Canonical splice site variant predicted to result in a null allele in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 11528394, 29607243) -