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