IGH clonality detection by PCR and capillary electrophoresis
CPT Code(s)
81261: IGH; G0452-26
Synonym(s)
Hematopathology, DNA, AIDS
Performed
Molecular Diagnostics Laboratory
Methodology
DNA is isolated and amplified by PCR using BIOMED-2 primers targeting the VH framework 1,
2, 3, DH and JH sequences of the IGH gene. The gene rearrangements are detected by analyzing
the PCR products by capillary gel electrophoresis.
Critical Values
The assay sensitivity for detection of clonal B-cell populations is 5% of lymphocytes.
Minimum Specimen Requirements
Collect
- Peripheral blood (PB): 3-5 mL, in purple top (sodium EDTA) tube; yellow top (ACD)
tube acceptable. - Bone marrow aspirate (BM): 1-3 mL, drawn into a syringe containing anticoagulant and
then delivered in purple top tube (EDTA). - Fresh or frozen tissue: fresh tissue should be obtained in a sterile manner, and a minimum
3 mm3
of tissue is required. Put fresh tissues in culture medium or snap freeze (see
transport section below). - Formalin-fixed paraffin-embedded (FFPE) tissue blocks: send FFPE tissue blocks to the
lab, or contact lab for instructions about cutting sections for molecular studies.
Transport
- PB or BM samples should be delivered immediately to the lab at 2-8°C (wet ice or cold
packs). PB and BM specimens should not be frozen. - Fresh tissue samples should be delivered at room temperature in RPMI culture medium to
the lab within 3 hours of collection, or snap frozen in liquid nitrogen at -70°C and packed
in dry ice for delivery. Please do not allow frozen tissues to thaw. - Formalin-fixed paraffin embedded (FFPE) tissue blocks can be delivered at room
temperature.
Stability
PB or BM samples: ambient – 1 hour; refrigerated – 48 hours.
Unacceptable Samples
- Serum or plasma; frozen PB or BM; clotted blood; severely hemolyzed samples
- Tissue samples fixed in Zenker’s, B5, or Bouin’s fixatives
- Bone marrow biopsies decalcified in formic acid
Turnaround time
Five to seven working days