CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication
2004935
 
Ordering Recommendation
Order to confirm the clinical diagnosis of a CDKL5 mutation-related disorder (eg, infantile spasm syndrome or MECP2-negative atypical Rett syndrome).
Mnemonic
CDKL5 FGA
Methodology
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Performed
Varies
Reported
Within 35 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory.
Specimen Required
Patient Preparation
 
Collect
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Transport 3 mL whole blood. (Min: 2 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
 
Remarks
 
Stability
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
Interpretive Data
Background Information for CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication:
Characteristics:
Vary widely but may include early onset intractable seizures, severe developmental delay, with females often exhibiting features of Rett syndrome.
Incidence
: Unknown; more frequent in females than males.
Inheritance:
X-linked dominant; reported cases are de novo.
Penetrance:
100 percent.
Cause:
Pathogenic CDKL5 gene mutations.
Clinical Sensitivity:
Approximately 17 percent in females with infantile spasms or seizures.
Methodology:
Bidirectional sequencing of the CDKL5 coding region and intron-exon boundaries. Multiplex ligation-dependent probe amplification (MLPA) to detect large CDKL5 coding region deletions/duplications.
Analytical Sensitivity and Specificity of Sequencing and MLPA
: 99 percent.
Limitations
: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. Large deletions/duplications of exon 3 will not be detected. The breakpoints of large deletions/duplications will not be determined.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note
CPT Code(s)
81405; 81406
Components
Component Test Code*Component Chart Name
2004936CDKL5-Related Disorder Seq,DelDup Spec
2004937CDKL5-Related Disorder Seq,DelDup Interp
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, contact interface support at interface.support@aruplab.com.
Cross References
  • Atypical Rett (CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication)
  • Epileptic Encephalopathy, Early Infantile 2 (CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication)
  • Infantile Spasms/Atypical Rett (CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication)
  • Rett-Like Syndrome (CDKL5-Related Disorders (CDKL5) Sequencing and Deletion/Duplication)