The BIRC6 gene encodes the Bruce (Apollon) protein. This belongs to the III class of Inhibitors of the Apoptosis Protein (IAP) and demonstrates anti-apoptotic activity (binding, inhibiting and degrading the caspases). Moreover, the Bruce protein shows multilevel activities and additional functions. The Bruce protein is involved in the maintenance of cell viability, and it is also suggested that it plays an important role in cell proliferation and diversification. Many researchers have noticed elevated BIRC6 gene expression in cell lines of brain cancer and ovarian carcinoma, leukemia, breast cancer and even in colorectal cancer tissues. Resistance to chemotherapy-inducted apoptosis in cancers characterized by BIRC6 gene over-expression was also reported. The aim of the study was to assess the BIRC6 gene expression in peripheral blood lymphocytes of patients diagnosed with chronic lymphocytic leukemia.