rs1555951993

Positions:

• chrX-41339045-A-G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2 PP3_Moderate PP5_Very_Strong

The NM_001363819.1(DDX3X):​c.-446A>G variant causes a 5 prime UTR premature start codon gain 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: DDX3X NM_001363819.1 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.12

Genes affected

DDX3X (HGNC:2745): (DEAD-box helicase 3 X-linked) The protein encoded by this gene is a member of the large DEAD-box protein family, that is defined by the presence of the conserved Asp-Glu-Ala-Asp (DEAD) motif, and has ATP-dependent RNA helicase activity. This protein has been reported to display a high level of RNA-independent ATPase activity, and unlike most DEAD-box helicases, the ATPase activity is thought to be stimulated by both RNA and DNA. This protein has multiple conserved domains and is thought to play roles in both the nucleus and cytoplasm. Nuclear roles include transcriptional regulation, mRNP assembly, pre-mRNA splicing, and mRNA export. In the cytoplasm, this protein is thought to be involved in translation, cellular signaling, and viral replication. Misregulation of this gene has been implicated in tumorigenesis. This gene has a paralog located in the nonrecombining region of the Y chromosome. Pseudogenes sharing similarity to both this gene and the DDX3Y paralog are found on chromosome 4 and the X chromosome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2014]

DDX3X (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.881
• PP5: Variant X-41339045-A-G is Pathogenic according to our data. Variant chrX-41339045-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 545446.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DDX3X	NM_001356.5	c.113A>G	p.Tyr38Cys	missense_variant	3/17	ENST00000644876.2	NP_001347.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DDX3X	ENST00000644876.2	c.113A>G	p.Tyr38Cys	missense_variant	3/17		NM_001356.5	ENSP00000494040.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 951166 Hom.: 0 Cov.: 17 AF XY: 0.00 AC XY: 0 AN XY: 282968

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Intellectual disability, X-linked 102 Pathogenic:3

Likely pathogenic, criteria provided, single submitter	clinical testing	Johns Hopkins Genomics, Johns Hopkins University	Apr 07, 2021	This DDX3X variant (rs1555951993) is absent in a large population dataset and has an entry in ClinVar. Two bioinformatics tools queried predict that p.Tyr38Cys would be damaging, while another predicts it would be tolerated. The tyrosine residue at this position is strongly conserved across the vertebrate species assessed. This variant is not predicted to affect normal exon 3 splicing, although this has not been confirmed experimentally to our knowledge. We consider c.113A>G to be likely pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Equipe Genetique des Anomalies du Developpement, Université de Bourgogne	Apr 19, 2017	- -
Pathogenic, criteria provided, single submitter	research	Laboratory of Human Genetics, Universidade de São Paulo	Mar 16, 2022	Variant disclosed in a girl with intellectual disability and X-chromosome inactivation skewing. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 13, 2022

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 38 of the DDX3X protein (p.Tyr38Cys). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of an X-linked intellectual disability syndrome (Invitae). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 545446). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.67	D;D;.;T;.;.;.;.;.;.;.;.;.
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	.;.;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.53	D
MetaRNN	Pathogenic	0.88	D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.11	T
MutationAssessor	Uncertain	2.6	M;M;.;.;.;.;.;.;.;.;.;.;.
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-7.6	.;.;.;.;D;.;.;.;.;.;.;.;.
REVEL	Uncertain	0.63
Sift4G	Pathogenic	0.0	.;D;D;D;D;.;.;.;.;.;.;.;.
Polyphen		0.98	D;D;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.74, 0.71, 0.74, 0.98
MutPred		0.56		Loss of phosphorylation at Y38 (P = 0.0384);Loss of phosphorylation at Y38 (P = 0.0384);Loss of phosphorylation at Y38 (P = 0.0384);Loss of phosphorylation at Y38 (P = 0.0384);Loss of phosphorylation at Y38 (P = 0.0384);Loss of phosphorylation at Y38 (P = 0.0384);.;Loss of phosphorylation at Y38 (P = 0.0384);.;.;Loss of phosphorylation at Y38 (P = 0.0384);.;.;
MVP		0.93
MPC		2.4
ClinPred		0.99	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.72
gMVP		0.81

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.20		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.20		Position offset: -6

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555951993; hg19: chrX-41198298; COSMIC: COSV67864387; COSMIC: COSV67864387;