Carrier screening or diagnostic testing for Canavan disease for individuals of Ashkenazi Jewish descent.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Plasma or serum. Specimens collected in sodium heparin or lithium heparin tubes.
- Ambient: 72 hours; Refrigerated: 2 weeks; Frozen: 1 month
Characteristics: Canavan Disease is a neurodegenerative brain disorder that results in macrocephaly and lack of head control by 3 to 5 months of age. This progresses to a failure to achieve sitting, ambulation, or speech, and eventually leads to death typically in early childhood to teenage years.
Incidence: 1 in 10,000 Ashkenazi Jewish individuals.
Inheritance: Autosomal recessive.
Cause: ASPA pathogenic variants.
Variants Tested: c.433-2A>G, p.Y231X (c.693C>A), p.E285A (c.854A>C), and p.A305E (c.914C>A).
Clinical Sensitivity: 99 percent in Ashkenazi Jewish individuals; 55 percent in other ethnicities.
Methodology: Polymerase chain reaction (PCR) and fluorescence monitoring.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Variants other than those tested will not be detected. Diagnostic errors can occur due to rare sequence variations.
|Component Test Code*||Component Chart Name||LOINC|
|0051455||Canavan Disease (ASPA), Allele 1||21081-5|
|0051456||Canavan Disease (ASPA), Allele 2||21081-5|
|0051457||Canavan Disease (ASPA), Interpretation||46990-8|
|2001299||Canavan Disease (ASPA), Specimen||31208-2|