chrX-18584332-G-T

Variant names:

• chrX-18584332-G-T
• rs267606715
• NM_001323289.2:c.533G>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_001323289.2(CDKL5):​c.533G>T​(p.Arg178Leu) variant causes a missense 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 Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R178Q) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 22)
• Consequence: CDKL5 NM_001323289.2 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.19
• Publications: 0 publications found

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]

CDKL5 Gene-Disease associations (from GenCC):

• CDKL5 disorder

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• developmental and epileptic encephalopathy, 2

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• atypical Rett syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• precocious puberty

  Inheritance: XL Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PM1: In a hotspot region, there are 16 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_001323289.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-18584332-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 94113.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981
• PP5: Variant X-18584332-G-T is Pathogenic according to our data. Variant chrX-18584332-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 2159555.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDKL5	NM_001323289.2	c.533G>T	p.Arg178Leu	missense_variant	Exon 8 of 18	ENST00000623535.2	NP_001310218.1
CDKL5	NM_001037343.2	c.533G>T	p.Arg178Leu	missense_variant	Exon 9 of 22		NP_001032420.1
CDKL5	NM_003159.3	c.533G>T	p.Arg178Leu	missense_variant	Exon 8 of 21		NP_003150.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDKL5	ENST00000623535.2	c.533G>T	p.Arg178Leu	missense_variant	Exon 8 of 18	1	NM_001323289.2	ENSP00000485244.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 27

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Oct 13, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 expected to disrupt CDKL5 protein function. This missense change has been observed in individual(s) with clinical features of CDKL5-related conditions (PMID: 30182498, 30776697, 31031587). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 178 of the CDKL5 protein (p.Arg178Leu). 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	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Benign	0.22	T;T;.;T;.;.
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.89	.;D;D;D;D;D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D
MetaSVM	Benign	-0.41	T
MutationAssessor	Benign	1.5	L;.;.;L;.;L
PhyloP100		8.2
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-7.0	D;.;.;D;.;.
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	D;.;.;D;.;.
Sift4G	Pathogenic	0.0	D;.;.;D;D;D
Polyphen		1.0	D;.;.;D;.;.
Vest4		0.97
MutPred		0.90		Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);
MVP		0.94
MPC		2.8
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.99
gMVP		0.98
Mutation Taster		=3/97	disease causing

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

Other links and lift over

dbSNP: rs267606715; hg19: chrX-18602452;