XL DLEU/LAMP/12cen consists of a green-labeled probe hybridizing to the centromere of chromosome 12, an orange-labeled probe hybridizing to the DLEU1/MIR15A/MIR16-1 gene region at 13q14.2 including D13S319 and an aqua-labeled probe hybridizing to the LAMP1 gene region at 13q34.

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.

The prognosis and clinical course of chronic lymphocytic leukemia (CLL) are heterogeneous. Conventional banding techniques in CLL are hampered by the low mitotic index of the neoplastic cells. The introduction of interphase cytogenetics using fluorescent in situ hybridization (FISH) has greatly increased the sensitivity of cytogenetic analyses. With FISH, abnormalities can be detected in more than 80% of patients by using a 4-probe panel for the detection of trisomy 12q13-15, and deletions 13q14, 17p13, and 11q22-23. An additional 10% of patients can be shown to carry a 6q21 deletion, 14q32 translocation, and partial trisomy 3q or 8q.
The most frequently deleted region in B-CLL is located in 13q14.3 distal to RB1. The minimal deleted region (MDR) is 350 kb in size and includes the gene loci for the mi-RNAs 15 and 16. CLL with 13q deletion as the sole cytogenetic abnormality usually have a good prognosis.
Deletions of chromosomal region 13q14 have also been reported in a variety of human tumors, including other types of lymphoid tumors and myeloid leukemias, as well as prostate, head and neck, and non-small-cell lung cancers.

Clinical Applications

• Chronic Lymphocytic Leukemia (CLL)

XL DLEU/LAMP/12cen hybridized to bone marrow cells. Three interphases are shown of which one shows a normal signal pattern of 2 orange, 2 green, and 2 blue signals, one nucleus shows a hemizygous, and a third one a homozygous deletion of DLEU (orange).

• Doehner et al (2000) N Engl J Med 34:1910-1916
• DeWald et al (2003) Brit J Haem 121:287-295
• Nelson at al (2007) Am J Clin Pathol 128:323-332