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, if possible.
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 theCDKL5 coding region and intron-exon boundaries. Multiplex ligation-dependent probe amplification (MLPA) to detect large CDKL5 coding regiondeletions/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.





See Compliance Statement C: www.aruplab.com/CS
Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test; however, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
 
Note
 
CPT Code(s)
81405; 81406
Components
Component Test Code*Component Chart NameLOINC
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, please click the sidebar link to access the Interface Map.
Aliases
  • Atypical Rett
  • Epileptic Encephalopathy, Early Infantile 2
  • Infantile Spasms/Atypical Rett
  • Rett-Like Syndrome