rs1557052542

Variant names:

• chrX-32816504-T-A
• rs1557052542
• NM_004006.3:c.494A>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_004006.3(DMD):​c.494A>T​(p.Asp165Val) variant causes a missense change involving the alteration of a conserved nucleotide. 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D165Y) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 23)
• Consequence: DMD NM_004006.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 8.01
• Publications: 1 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: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 12 uncertain in NM_004006.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DMD	NM_004006.3	c.494A>T	p.Asp165Val	missense_variant	Exon 6 of 79	ENST00000357033.9	NP_003997.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DMD	ENST00000357033.9	c.494A>T	p.Asp165Val	missense_variant	Exon 6 of 79	1	NM_004006.3	ENSP00000354923.3

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Becker muscular dystrophy Pathogenic:1

-

Institute of Human Genetics, University of Wuerzburg

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Duchenne muscular dystrophy Uncertain:1

Jun 06, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Experimental studies have shown that this missense change increases protein aggregation and thermal denaturation but does not significantly affect actin-binding affinity (PMID: 20457930). This variant has been reported in individuals affected with Becker muscular dystrophy (PMID: 12632325, Invitae). This variant is not present in population databases (ExAC no frequency). This sequence change replaces aspartic acid with valine at codon 165 of the DMD protein (p.Asp165Val). The aspartic acid residue is highly conserved and there is a large physicochemical difference between aspartic acid and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.82
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.90	.;D;.;.;D
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;.;D;D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
PhyloP100		8.0
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-6.7	.;D;.;D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	.;D;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Polyphen		1.0	.;D;.;.;D
Vest4		0.99
MutPred		0.94		.;.;Gain of helix (P = 0.2059);Gain of helix (P = 0.2059);.;
MVP		1.0
MPC		0.13
ClinPred		1.0	D
GERP RS		5.5
gMVP		0.95
Mutation Taster		=15/85	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1557052542; hg19: chrX-32834621;