X-49075947-T-C

Variant names:

• chrX-49075947-T-C
• rs886041693
• NM_001029896.2:c.437-2A>G

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001029896.2(WDR45):​c.437-2A>G variant causes a splice acceptor, intron 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: WDR45 NM_001029896.2 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.45

Genes affected

WDR45 (HGNC:28912): (WD repeat domain 45) This gene encodes a member of the WD repeat protein family. WD repeats are minimally conserved regions of approximately 40 amino acids typically bracketed by gly-his and trp-asp (GH-WD), which may facilitate formation of heterotrimeric or multiprotein complexes. Members of this family are involved in a variety of cellular processes, including cell cycle progression, signal transduction, apoptosis, and gene regulation. This gene has a pseudogene at chromosome 4q31.3. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene, but the biological validity and full-length nature of some variants have not been determined. [provided by RefSeq, Jul 2008]

ENSG00000288053 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.2, offset of 22, new splice context is: ctctgtgacctctgccccAGcct. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-49075947-T-C is Pathogenic according to our data. Variant chrX-49075947-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 280501.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-49075947-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
WDR45	NM_001029896.2	c.437-2A>G		splice_acceptor_variant, intron_variant	Intron 6 of 10	ENST00000376372.9	NP_001025067.1
WDR45	NM_007075.4	c.440-2A>G		splice_acceptor_variant, intron_variant	Intron 7 of 11		NP_009006.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
WDR45	ENST00000376372.9	c.437-2A>G		splice_acceptor_variant, intron_variant	Intron 6 of 10	1	NM_001029896.2	ENSP00000365551.3
ENSG00000288053	ENST00000376358.4	c.131-2A>G		splice_acceptor_variant, intron_variant	Intron 3 of 7	2		ENSP00000365536.3

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurodegeneration with brain iron accumulation 5 Pathogenic:1

Jun 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects an acceptor splice site in intron 7 of the WDR45 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in WDR45 are known to be pathogenic (PMID: 23176820, 24368176, 24621584, 25744623, 26790960, 27030146, 27652284, 28554332). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with WDR45-related conditions (PMID: 26790960). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 280501). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Oct 13, 2016

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.440-2 A>G splice site variant in the WDR45 gene has been previously reported as a de novo variant in a female with Rett-like syndrome exhibiting developmental delay, microcephaly, seizures and stereotypic hand movements (Hoffjan et al., 2016). It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This pathogenic variant destroys the canonical splice acceptor site in intron 7, and is expected to cause abnormal gene splicing. Therefore, the presence of the c.440-2 A>G variant is consistent with a diagnosis of WDR45-related disorder -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Uncertain	-0.040
CADD	Pathogenic	32
DANN	Uncertain	0.98
FATHMM_MKL	Pathogenic	0.98	D
GERP RS		3.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.96
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.40		Position offset: 31
DS_AL_spliceai		0.97		Position offset: -2

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

Publications

LitVar

Other links and lift over

dbSNP: rs886041693; hg19: chrX-48933606;