XL IGH BA consists of an orange-labeled probe partly covering the constant region of the IGH locus at 14q32.3 and a green-labeled probe hybridizing to the variable distal region of the IGH locus at 14q32.3.

Probe maps are created in accordance with the intended purpose of the product. Solid colored bars do not necessarily indicate that the probe fully covers the indicated genomic region. Therefore, caution is advised when interpreting results generated through off-label use. Probe map details based on UCSC Genome Browser GRCh37/hg19. Map components not to scale. Further information is available on request.

Chromosomal translocations affecting the immunglobulin heavy chain (IGH) locus at 14q32.3 are recurrent in many types of lymphomas and plasma cell neoplasms. The consequence of these rearrangements is the dysregulation of genes juxtaposed to transcriptional enhancers in the IGH locus.
Burkitt lymphoma (BL) is a rare but fast growing type of non-Hodgkin lymphoma (NHL). The translocation between the MYC gene locus at 8q24 and the immunoglobulin genes (IG) for the kappa light chain at 2p12 (IGK), for the heavy chain at 14q32 (IGH) or for the lambda light chain at 22q11 (IGL) juxtapose the MYC gene to an IG enhancer. About 80% of BL patients have the MYC rearrangement t(8;14) while approximately 10% show a translocation between the MYC gene region and IGK or IGL.
Follicular lymphoma (FL) is the most common indolent form of the NHL. The reciprocal translocation t(14;18) is observed in about 85% of patients with FL and results in overexpression of the BCL-2 protein which is involved in the regulation of apoptosis.
About 1% of all cancers and 10% of hematologic malignancies are caused by multiple myelomas (MM). Translocations affecting the IGH locus are observed in about 40% of MM cases.

Due to the telomeric position of the IGH locus, 14q32.3 translocations may be easily missed by conventional cytogenetics. FISH is therefore a valuable tool in the diagnostic of translocations affecting the IGH locus.

Clinical Applications

• Multiple Myeloma and Plasma Cell Neoplasms (MM)
• Non-Hodgkin Lymphomas (NHL)
• Acute Lymphoblastic Leukemia (ALL)
• Chronic Lymphocytic Leukemia (CLL)

XL IGH BA hybridized to lymphocytes. Two normal interphases are shown.

• Freedman (2014) Am J Hematol 89:429-436
• Rajan and Rajkumar (2015) Blood Canc J 5:1-7
• Nguyen et al (2017) Genes 8:1-23