X-32389496-C-T

Position:

• chrX-32389496-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2 PP3 PP5_Very_Strong

The NM_004006.3(DMD):​c.4518+5G>A variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 22)
• Consequence: DMD NM_004006.3 splice_region, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 4.35

Genes affected

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Multiple lines of computational evidence support a deleterious effect 4: Cadd, dbscSNV1_ADA, dbscSNV1_RF, max_spliceai [when BayesDel_noAF, Dann was below the threshold]
• PP5: Variant X-32389496-C-T is Pathogenic according to our data. Variant chrX-32389496-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 94630.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-32389496-C-T is described in Lovd as [Pathogenic]. Variant chrX-32389496-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DMD	NM_004006.3	c.4518+5G>A		splice_region_variant, intron_variant		ENST00000357033.9	NP_003997.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DMD	ENST00000357033.9	c.4518+5G>A		splice_region_variant, intron_variant		1	NM_004006.3	ENSP00000354923.3

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Duchenne muscular dystrophy Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	3billion	Feb 23, 2023	This intron variant is not observed in the gnomAD v2.1.1 dataset. Functional studies provide strong evidence of the variant having a damaging effect on the gene or gene product (PMID: 15979033). In silico tools predict the variant to alter splicing and produce an abnormal transcript (SpliceAI: 0.87). The variant has been observed in multiple (>3) similarly affected unrelated individuals (PMID: 15979033, 21969337, 23453023, 28859693). The variant has been reported at least twice as pathogenic without evidence for the classification (ClinVar ID: VCV000094630). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 16, 2020	For these reasons, this variant has been classified as Pathogenic. This sequence change falls in intron 32 of the DMD gene. It does not directly change the encoded amino acid sequence of the DMD protein, but it affects a nucleotide within the consensus splice site of the intron. This variant is not present in population databases (ExAC no frequency). Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Experimental studies have shown that this variant disrupts mRNA splicing (PMID: 15979033). This variant has been observed in individual(s) with DMD-related muscular dystrophy (PMID: 15979033, 21969337, 23453023, 28859693). ClinVar contains an entry for this variant (Variation ID: 94630). -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Jul 17, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.19
CADD	Pathogenic	26
DANN	Benign	0.94

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.99
SpliceAI score (max)		0.87		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.76		Position offset: -23
DS_DL_spliceai		0.87		Position offset: 5

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs398123960; hg19: chrX-32407613;