X-32365187-C-G

Position:

• chrX-32365187-C-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BS2_Supporting

The NM_004006.3(DMD):​c.4858G>C​(p.Glu1620Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000273 in 1,097,194 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 2 hemizygotes in GnomAD. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0000027 (0 hom. 2 hem.)
• Consequence: DMD NM_004006.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 7.71

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]

DMD (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• BS2: High Hemizygotes in GnomAdExome4 at 2 XL geneVariant has number of hemizygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DMD	NM_004006.3	c.4858G>C	p.Glu1620Gln	missense_variant	35/79	ENST00000357033.9	NP_003997.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DMD	ENST00000357033.9	c.4858G>C	p.Glu1620Gln	missense_variant	35/79	1	NM_004006.3	ENSP00000354923.3

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome AF: 0.00000273 AC: 3 AN: 1097194 Hom.: 0 Cov.: 30 AF XY: 0.00000551 AC XY: 2 AN XY: 362746

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: 0.00000357

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 22

EpiCase AF: 0.0000546

EpiControl AF: 0.00

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.

Jan 17, 2020

- -

Duchenne muscular dystrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 17, 2023

This sequence change replaces glutamic acid, which is acidic and polar, with glutamine, which is neutral and polar, at codon 1620 of the DMD protein (p.Glu1620Gln). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DMD-related conditions. ClinVar contains an entry for this variant (Variation ID: 1047689). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt DMD protein function with a negative predictive value of 95%. 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	Benign	0.19
BayesDel_addAF	Uncertain	0.078	D
BayesDel_noAF	Benign	-0.13
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.30	.;T;.;.;.
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.89	D;.;D;D;D
M_CAP	Pathogenic	0.70	D
MetaRNN	Uncertain	0.52	D;D;D;D;D
MetaSVM	Benign	-0.41	T
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	-1.6	.;N;.;N;N
REVEL	Benign	0.24
Sift	Benign	0.033	.;D;.;D;T
Sift4G	Benign	0.096	T;T;T;T;T
Polyphen		1.0	.;D;.;.;.
Vest4		0.51
MutPred		0.53		.;.;Gain of MoRF binding (P = 0.0278);Gain of MoRF binding (P = 0.0278);.;
MVP		0.75
MPC		0.055
ClinPred		0.90	D
GERP RS		5.8
gMVP		0.40

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060502645; hg19: chrX-32383304;