rs267608423

Positions:

• chrX-18564475-A-G

Variant summary

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

The NM_001323289.2(CDKL5):​c.100-2A>G variant causes a splice acceptor, intron change. 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: 21)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: CDKL5 NM_001323289.2 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3 O:1
• Conservation: PhyloP100: 4.01

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 Pathogenic. Variant got 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-18564475-A-G is Pathogenic according to our data. Variant chrX-18564475-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 156073.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
CDKL5	NM_001323289.2	c.100-2A>G		splice_acceptor_variant, intron_variant		ENST00000623535.2	NP_001310218.1
CDKL5	NM_001037343.2	c.100-2A>G		splice_acceptor_variant, intron_variant			NP_001032420.1
CDKL5	NM_003159.3	c.100-2A>G		splice_acceptor_variant, intron_variant			NP_003150.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDKL5	ENST00000623535.2	c.100-2A>G		splice_acceptor_variant, intron_variant		1	NM_001323289.2	ENSP00000485244.1

Frequencies

GnomAD3 genomes Cov.: 21

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1049503 Hom.: 0 Cov.: 20 AF XY: 0.00 AC XY: 0 AN XY: 326711

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.: 21

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Developmental and epileptic encephalopathy, 2 Pathogenic:1

Pathogenic, no assertion criteria provided

curation

RettBASE

Mar 13, 2014

Splice site mutation causing skipping of exon 4 -

CDKL5 disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

curation

Centre for Population Genomics, CPG

Jul 15, 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). This variant has been identified as a de novo occurrence in an individual with CDKL5 disorder without confirmation of paternity and maternity (PM6, PMID: 19793311). This variant is absent from gnomAD (PM2_Supporting). -

Developmental and epileptic encephalopathy, 2;CN128785:Angelman syndrome-like Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 14, 2019

For these reasons, this variant has been classified as Pathogenic. Donor and acceptor splice site variants typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CDKL5 are known to be pathogenic (PMID: 22872100). Experimental studies have shown that this variant disrupts mRNA splicing (PMID: 19793311). This variant has been observed in individuals with early-onset seizures (PMID: 19793311). ClinVar contains an entry for this variant (Variation ID: 156073). This variant is not present in population databases (ExAC no frequency). This sequence change affects an acceptor splice site in intron 3 of the CDKL5 gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product. -

not provided Other:1

not provided, flagged submission

literature only

RettBASE

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.20
CADD	Pathogenic	28
DANN	Uncertain	0.99
FATHMM_MKL	Uncertain	0.93	D
GERP RS		4.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.99		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: rs267608423; hg19: chrX-18582595;