BLAU SYNDROME (NOD2/CARD15 COMPLETE GENE)
Gene Symbol: NOD2
Chromosomal Locus: 16q12.1
Protein: Nucleotide-Binding Oligomerization Domain Protein 2 or Caspase Recruitment Domain-Containing Protein 15
TURNAROUND TIME: 4 weeks
TESTING METHODOLOGY: Polymerase chain reaction (PCR) followed by sequencing all 12 exon coding regions and the intron/exon borders.
- Collect: Prefer two 5ml whole blood EDTA (lavender top) tube.
- Min. Collection: 0.7 ml whole blood EDTA.
- Transport: blood EDTA at Room Temp shipped regular next day air (No Saturday delivery; store specimen at 4°C and ship Monday).
- Stability: Ambient: up to 7 days; Refrigerated: 2 weeks. Frozen: unacceptable
- Unacceptable Conditions: Serum. Frozen or severely hemolyzed blood. Clotted blood.
- Prenatal testing: Direct: 5ml direct unspun amniotic fluid or 15mg CVS tissue with a backup flask growing. Culture: confluent T25 flask. Maternal blood sample is required for maternal cell contamination studies.
Counseling and informed consent are recommended for genetic testing. A consent form
is available as a resource but not required.
Incidence: Uncertain but rare
Inheritance: Autosomal dominant
Disease Characteristics: Blau syndrome is classically characterized by early-onset granulomatous arthritis, uveitis and skin rash with camptodactyly. This condition shows a high degree of variable expression. Patients can often display only one symptom or have a unique presentation. The symptoms can overlap with Crohn Syndrome.
Molecular Genetic Mechanism: A variety of mutations have been cited throughout the entire gene.
Analytical Sensitivity: 99%.
Test Limitations: Mutations that are not in the coding sequence of the NOD2 gene will not be detected. Rare diagnostic errors can occur due to primer / probe site mutations or rare polymorphisms.
INDICATIONS FOR USE:
- To confirm a clinical diagnosis.
- To determine whether a patient may respond well to glucocorticoid treatment.
- To help differentiate Blau and Crohn syndrome patients.
- Individuals at risk who wish prenatal diagnosis.