Detection of immunoglobulin heavy chain gene rearrangements in hematologic malignancies.

B-cell precursors undergo a unique somatic immunoglobulin heavy chain gene rearrangement process. The generated VHDHJH junction is a successful marker in lymphoproliferative malignancies at initial diagnosis for detection of clonality and during treatment for monitoring minimal residual disease. VHDHJH errors are often involved in recurring structural chromosomal aberrations of lymphoid malignancies, with consequent deregulated expression of the juxtaposed oncogenes, e.g., c-myc, bcl-2 or CCND1. Besides cytogenetics, a variety of molecular techniques are becoming increasingly established, including Southern blotting, PCR and real-time PCR, as well as fluorescence in situ hybridisation. Different approaches may be chosen to evaluate lymphoid malignancies either at diagnosis or follow-up in the light of increasing relevance and proven clinical utility.