ARUP's Laboratory Test Directory

CDKL5-Related Disorders (CDKL5) Deletion/Duplication : 2004927
[ image for: Patient History for Rett Syndrome (MECP2) or CDKL5-Related Disorders (CDKL5) Testing]
Patient History for Rett Syndrome (MECP2) or CDKL5-Related Disorders (CDKL5) Testing
  


Mnemonic: CDKL5 DD

Ordering Recommendation: Order to confirm the clinical diagnosis of a CDKL5 mutation-related disorder (eg, infantile spasm syndrome or MECP2-negative atypical Rett syndrome).
Methodology: Polymerase Chain Reaction/Multiplex Ligation-dependent Probe Amplification
Performed: Varies
Reported: Within 14 days
Specimen Required: Collect: Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation: Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature: Refrigerated.

Stability (collection to initiation of testing): Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Interpretive Data: Background Information for CDKL5-Related Disorders (CDKL5) 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:
Unknown.
Methodology:
Multiplex ligation-dependent probe amplification (MLPA) to detect large CDKL5 coding region deletions/duplications.
Analytical Sensitivity and Specificity:
99 percent.
Limitations
: Rare diagnostic errors can occur due to probe site mutations. Single base pair substitutions, small deletions/duplications, 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
CPT Code(s): 81479
Cross References: Atypical Rett (CDKL5)  (CDKL5-Related Disorders (CDKL5) Deletion/Duplication) , Epileptic Encehpalopathy, Early Infantile 2 (CDKL5-Related Disorders (CDKL5) Deletion/Duplication) , Infantile Spasms/Atypical Rett (CDKL5-Related Disorders (CDKL5) Deletion/Duplication) , Rett-Like Syndrome (CDKL5-Related Disorders (CDKL5) Deletion/Duplication)