CDKL2

Chr 4

cyclin dependent kinase like 2

Also known as: KKIAMRE, P56

CDKL2 encodes a serine/threonine protein kinase that localizes primarily to the cytoplasm with some nuclear presence. Mutations cause neurodevelopmental disorders with intellectual disability, seizures, and developmental delays, inherited in an autosomal dominant pattern. The gene shows relatively low constraint to loss-of-function variants, suggesting the associated phenotypes may involve diverse mutational mechanisms.

OMIMResearchSummary from RefSeq
MultiplemechanismLOEUF 1.43
Clinical SummaryCDKL2
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
24 unique Pathogenic / Likely Pathogenic· 74 VUS of 111 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.43LOEUF
pLI 0.000
Z-score -0.11
OE 1.02 (0.751.43)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.25Z-score
OE missense 1.04 (0.941.16)
263 obs / 252.0 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE1.02 (0.751.43)
00.351.4
Missense OE1.04 (0.941.16)
00.61.4
Synonymous OE1.01
01.21.6
LoF obs/exp: 25 / 24.4Missense obs/exp: 263 / 252.0Syn Z: -0.10
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
limitedCDKL2-related neurodevelopmental disorderOTHERAD
DN
0.6744th %ile
GOF
0.74top 25%
LOF
0.4331th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median
DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

111 submitted variants in ClinVar

Classification Summary

Pathogenic23
Likely Pathogenic1
VUS74
Likely Benign5
23
Pathogenic
1
Likely Pathogenic
74
VUS
5
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
23
0
23
Likely Pathogenic
0
1
0
0
1
VUS
0
69
5
0
74
Likely Benign
0
5
0
0
5
Benign
0
0
0
0
0
Total075280103

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

CDKL2 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
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