chrX-18625245-C-T

Position:

• chrX-18625245-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_001323289.2(CDKL5):​c.2494C>T​(p.Gln832*) variant causes a stop gained, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 22)
• Consequence: CDKL5 NM_001323289.2 stop_gained, splice_region
• Scores: Splicing: ADA: 0.9979
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 5.43

Genes affected

CDKL5 (HGNC:11411): (cyclin dependent kinase like 5) This gene is a member of Ser/Thr protein kinase family and encodes a phosphorylated protein with protein kinase activity. Mutations in this gene have been associated with X-linked infantile spasm syndrome (ISSX), also known as X-linked West syndrome, and Rett syndrome (RTT). Alternate transcriptional splice variants have been characterized. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.135 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-18625245-C-T is Pathogenic according to our data. Variant chrX-18625245-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 189573.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CDKL5	NM_001323289.2	c.2494C>T	p.Gln832*	stop_gained, splice_region_variant	17/18	ENST00000623535.2	NP_001310218.1
CDKL5	NM_001037343.2	c.2494C>T	p.Gln832*	stop_gained, splice_region_variant	18/22		NP_001032420.1
CDKL5	NM_003159.3	c.2494C>T	p.Gln832*	stop_gained, splice_region_variant	17/21		NP_003150.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDKL5	ENST00000623535.2	c.2494C>T	p.Gln832*	stop_gained, splice_region_variant	17/18	1	NM_001323289.2	ENSP00000485244.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 2 Pathogenic:1

Pathogenic, no assertion criteria provided

curation

RettBASE

Mar 13, 2014

Truncation causing loss of C-terminus including potential nuclear export signal, also not in 1000 genomes or ESP -

CDKL5 disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

curation

Centre for Population Genomics, CPG

Aug 21, 2024

This variant has been collected from RettBASE and curated to current modified ACMG/AMP criteria. Based on the classification scheme defined by the ClinGen Rett/Angelman-like Expert Panel for Rett/AS-like Disorders Specifications to the ACMG/AMP Variant Interpretation Guidelines VCEP 3.0, this variant is classified as pathogenic. At least the following criteria are met: Predicted to result in loss of function, and LOF is a known mechanism of disease (PVS1). Has been observed in at least 2 individuals with phenotypes consistent with CDKL5 disorder (PS4_Supporting).PMID: 23647072, 25951140 This variant is absent from gnomAD V4 (PM2_Supporting). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	38
DANN	Uncertain	1.0
FATHMM_MKL	Uncertain	0.96	D
Vest4		0.90
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
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: rs17857094; hg19: chrX-18643365;