ARL11, also known as ADP Ribosylation factor-Like Tumor Suppressor gene 1 (ARLTS1) was described as a potential low-penetrance tumor suppressor gene in different types of cancers, such as breast cancer, melanoma and chronic lymphocytic leukemia (Calin et al., 2005). The gene discussed is ARL11; the disease is B-cell chronic lymphocytic leukemia.