A 68-year-old male was first diagnosed with B-cell chronic lymphocytic leukemia (B-CLL) in July 2006, based on incidental finding of lymphocytosis, blood film morphology, and the typical lymphocyte surface markers with positive CD19, CD5, CD23, and weak expression of surface lambda. The gene discussed is FCER2; the disease is B-cell chronic lymphocytic leukemia.