Calreticulin Exon 9 Mutation
General Information
- Lab Name
- Calreticulin Exon 9 Mutation
- Lab Code
- CALR
- Epic Ordering
- Calreticulin Exon 9 Mutation
- Description
Our qualitative test for CALR exon 9 insertion/deletion mutations is performed by PCR using purified genomic DNA with intron-located primers that flank and amplify exon 9 of CALR.
The somatic insertion/deletion mutations in exon 9 of the CALR gene have been associated with several chronic myeloproliferative disorders, including essential thrombocythemia (ET) and primary myelofibrosis (PMF) and infrequently other myeloid stem cell disorders. In the studies published to date, CALR mutations have been found in approximately 20-25% of ET patients, and 30-35% of PMF patients. Less commonly, this mutation may be found in some low grade myelodysplastic syndromes and other myeloid stem cell disorders.
The most common subtypes of CALR mutations reported include the type 1 mutation (52 base pair deletion) and the type 2 mutation (5 base pair insertion). For these mutation subtypes, additional Sanger sequencing will not be performed. For other mutation subtypes, specifically non-Type 1 and non-Type 2, sequencing will be performed to confirm the size of the deletion/insertion.
This testing can also be performed as part of JAK2 reflexive testing.
Limit of Detection: 2%
Limit of Detection Sanger sequencing: 20%
Hematopathology test request form found at Request Form
- Forms & Requisitions
- Synonyms
- CALR, Essential Thrombocythemia, Myeloproliferative Neoplasm, Primary Myelofibrosis
- Components
-
Code Name CALRSD CALR Exon 9 Mutation Spec Desc CALRRS CALR Exon 9 Mutation Result CALRBP CALR Exon 9 Mutation Size CALRIN CALR Exon 9 Mutation Interp CALRM CALR Exon 9 Mutation Method CALRGR CALR Exon 9 Case Number
Interpretation
- Method
PCR DNA amplification and size fractionated capillary electrophoresis
- Reference Range
- See individual components
- Guidelines
Ordering & Collection
- Specimen Type
- Blood, Bone Marrow, Fresh or Frozen Tissue, Fluids, Slides, Sorted cells
- Collection
-
Preferred:
Blood: 6mL in Lavender Top (EDTA)Bone Marrow: 1-2mL in Lavender Top (EDTA)
Tissue, Fluids or Sorted cells: Sterile container in RPMI
Slides: 10 unstained
Accepted:
Green Tops (Heparin), while green tops are accepted for testing, there is documentation that heparin can interfere with some PCR assays.Extracted DNA will only be accepted from CLIA certified laboratories.
Tissue from stained or cover-slipped slides
Unacceptable:
Specimens received beyond stability limit.
Specimens with low volume or inadequate WBC
Formalin-fixed paraffin embedded tissue (FFPE/PET)
Decalcified or unacceptable fixatives - Forms & Requisitions
- Handling Instructions
- Deliver samples to Hematopathology as soon as possible.
- If sample is older than 48 hours, please store at 2-6°C upon receipt and send refrigerated.
- Samples stored at room temperature or refrigerated older than 7 days will be rejected.
- Frozen samples should be shipped on dry ice.
- Quantity
-
requested: Blood: 6mL EDTA/BMA: 1-2mL EDTA/Slides: 10 unstained
minimum: Blood: 1mL EDTA/ BMA: 0.5mL EDTA/ Slides: 5 slides
Processing
- Processing
Send specimens to Hematopathology – Molecular department for processing.
The stability limit for Blood and Bone Marrow is 7 days, samples beyond this limit will be rejected.
Performance
- LIS Dept Code
- Molecular Hematopathology (MHP)
- Performing Location(s)
-
Other Hematopathology, Molecular
206-606-7060UW Hematopathology Laboratory, G7-800
Fred Hutchinson Cancer Center
825 Eastlake Avenue E.
Seattle, WA 98109Hematopathology, Molecular hours:
7:00 am - 5:30 pm M-F
8:00 am - 4:30 pm Saturday, closed on Sunday, and with reduced staffing on major holidays - Frequency
- Monday, Wednesday and Friday: Results available within 24hrs.
- Available STAT?
- No
Billing & Coding
- CPT codes
- 81219
- LOINC
- 35474-6
- Interfaced Order Code
- UOW2873