Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_ModeratePM2PP5_Moderate
The NM_004006.3(DMD):c.6913-11_6918delTTTCCTTTCAGGTTTCC(p.Val2305_Arg2307del) variant causes a splice acceptor, conservative inframe deletion, splice region, intron change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).
DMD (HGNC:2928): (dystrophin) This gene spans a genomic range of greater than 2 Mb and encodes a large protein containing an N-terminal actin-binding domain and multiple spectrin repeats. The encoded protein forms a component of the dystrophin-glycoprotein complex (DGC), which bridges the inner cytoskeleton and the extracellular matrix. Deletions, duplications, and point mutations at this gene locus may cause Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), or cardiomyopathy. Alternative promoter usage and alternative splicing result in numerous distinct transcript variants and protein isoforms for this gene. [provided by RefSeq, Dec 2016]
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.016820401 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant X-31875367-TGGAAACCTGAAAGGAAA-T is Pathogenic according to our data. Variant chrX-31875367-TGGAAACCTGAAAGGAAA-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 455926.Status of the report is criteria_provided_single_submitter, 1 stars.
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This variant is a deletion of the genomic region encompassing part of exon 48 (c.6913-11_6918del) of the DMD gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Loss-of-function variants in DMD are known to be pathogenic (PMID: 16770791, 25007885). This variant has not been reported in the literature in individuals with DMD-related disease. ClinVar contains an entry for this variant (Variation ID: 455926). This variant is not present in population databases (ExAC no frequency). -