X-32485002-A-G

Position:

• chrX-32485002-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_004006.3(DMD):​c.2720T>C​(p.Leu907Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000182 in 1,097,853 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. 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. L907R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0000018 (0 hom. 1 hem.)
• Consequence: DMD NM_004006.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 6.71

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.907

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DMD	NM_004006.3	c.2720T>C	p.Leu907Pro	missense_variant	21/79	ENST00000357033.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DMD	ENST00000357033.9	c.2720T>C	p.Leu907Pro	missense_variant	21/79	1	NM_004006.3	P4

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome AF: 0.00000182 AC: 2 AN: 1097853 Hom.: 0 Cov.: 30 AF XY: 0.00000275 AC XY: 1 AN XY: 363243

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000238

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Duchenne muscular dystrophy;C0878544:Cardiomyopathy;C0917713:Becker muscular dystrophy;na:Dystrophin deficiency Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Aug 12, 2019

- -

Duchenne muscular dystrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 27, 2021

This sequence change replaces leucine with proline at codon 907 of the DMD protein (p.Leu907Pro). The leucine residue is highly conserved and there is a moderate physicochemical difference between leucine and proline. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with DMD-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Uncertain	25
DANN	Pathogenic	1.0
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.79	T;.;T;T
M_CAP	Pathogenic	0.46	D
MetaRNN	Pathogenic	0.91	D;D;D;D
MetaSVM	Benign	-0.61	T
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.65	T
Sift4G	Uncertain	0.010	D;D;D;D
Polyphen		1.0	.;D;.;.
Vest4		0.88
MutPred		0.70		.;.;Loss of stability (P = 0.0118);Loss of stability (P = 0.0118);
MVP		0.99
MPC		0.13
ClinPred		0.97	D
GERP RS		4.8
gMVP		0.66

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060502654; hg19: chrX-32503119;