X-32518098-C-T

Variant names:

• chrX-32518098-C-T
• rs1060502636
• NM_004006.3:c.2202G>A

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_004006.3(DMD):​c.2202G>A​(p.Trp734*) variant causes a stop gained change. The variant was absent in control chromosomes in GnomAD project. 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.

• Frequency: Genomes: not found (cov: 22)
• Consequence: DMD NM_004006.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 4.27
• Publications: 0 publications found

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]

DMD Gene-Disease associations (from GenCC):

• Becker muscular dystrophy

  Inheritance: XL Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
• dilated cardiomyopathy 3B

  Inheritance: XL Classification: DEFINITIVE Submitted by: Ambry Genetics
• Duchenne and Becker muscular dystrophy

  Inheritance: XL Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• Duchenne muscular dystrophy

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, Orphanet
• progressive muscular dystrophy

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• non-syndromic X-linked intellectual disability

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• symptomatic form of muscular dystrophy of Duchenne and Becker in female carriers

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 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 X-32518098-C-T is Pathogenic according to our data. Variant chrX-32518098-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 409907.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DMD	NM_004006.3	c.2202G>A	p.Trp734*	stop_gained	Exon 18 of 79	ENST00000357033.9	NP_003997.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DMD	ENST00000357033.9	c.2202G>A	p.Trp734*	stop_gained	Exon 18 of 79	1	NM_004006.3	ENSP00000354923.3

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Duchenne muscular dystrophy Pathogenic:1

Aug 24, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

While this particular variant has not been reported in the literature, truncating variants in DMD are known to be pathogenic (PMID: 16770791). This sequence change creates a premature translational stop signal at codon 734 (p.Trp734*) of the DMD gene. It is expected to result in an absent or disrupted protein product. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	39
DANN	Uncertain	1.0
FATHMM_MKL	Uncertain	0.85	D
PhyloP100		4.3
Vest4		0.94
GERP RS		5.1
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1060502636; hg19: chrX-32536215;